Substituted thiophenes: compositions, processes of making, and uses in disease treatment and diagnosis

ABSTRACT

Substituted thiophenes, processes for their preparation, their use as medicament or diagnostic agent. The substituted thiophene derivatives have the following backbone structure: 
                         
Medicaments comprising compounds of this type are of use for preventing or treating various disorders, such as, respiratory disorders and snoring, acute and chronic disorders, disorders induced by ischemic and/or reperfusion events and by proliferative or fibrotic events, disorders of the central nervous system and lipid metabolism, diabetes, blood coagulation and infection by parasites.

This application is a divisional of U.S. Ser. No. 11/385,331 filed onMar. 21, 2006 which is a continuation of U.S. Ser. No. 10/448,851, filedMay 30, 2003, which claims the benefit of U.S. Provisional ApplicationNo. 60/415,788 filed Oct. 3, 2002 and benefit of priority from GermanApplication No. 10224892.3, filed Jun. 4, 2002.

FIELD OF THE INVENTION

The invention relates to the substituted thiophene compounds of formulaI useful for treating and/or preventing various disorders. Moreparticularly, the invention relates to the substituted thiophenecompounds of formula I possessing potent inhibitory properties on thesodium/proton exchanger of subtype 3 (“NHE3”), which makes the compoundsuseful, in the form of a medicament, for the treatment of respiratorydisorders and for the improving of the respiratory drive, for thetreatment of acute and chronic disorders, ischemic and/or reperfusiondisorders and disorders triggered by cellular proliferative or fibroticevents, and for the treatment of disorders of the central nervous systemand lipid metabolism, and diabetes, blood coagulation and infection byparasites.

BACKGROUND OF THE INVENTION

NHE3 is found in the body of various species, for example, in the gallbladder, the intestine and the kidney (Larry Fliegel et al., Biochem.Cell. Biol. 76: 735-741, 1998), but can also be detected in the brain(E. Ma et al., Neuroscience 79: 591-603).

The NHE3 inhibitors known to date are derived from compounds of theacylguanidine type (EP825178), of the norbornylamine type (DE199 60204), of the 2-guanidino-quinazoline type (WO 0179186) or of thebenzamidine type (WO0121582, WO172742). Squalamine, which has also beendescribed as NHE3 inhibitor (M. Donowitz et al. Am. J. Physiol. 276(Cell Physiol. 45): C136-C144), is, according to current understanding,not, unlike the compounds of formula I, effective immediately, butrather via an indirect mechanism and thus reaches its maximum potencyonly after one hour. Such NHE3 inhibitors which act by a differentmechanism are therefore suitable for use as combination partners for thepresent compounds according to the invention.

Clonidine, which is similar to the compounds described here, is known asa weak NHE inhibitor. However, its action on the NHE3 of the rat is,with a half-maximal inhibitory concentration (IC₅₀) of 620 μM, extremelymoderate. In contrast, it shows a certain selectivity for the NHE2 (J.Orlowski et al. J. Biol. Chem. 268, 25536). It would therefore be moreaccurate to refer to clonidine as an NHE2 inhibitor. In addition to theweak NHE action, clonidine has a high affinity for the adrenergic alpha2receptor and the imidazoline I1 receptor, mediating a strong hypotensiveaction (Ernsberger et al., Eur. J. Pharmacol. 134, 1, 1987).

Clonidine-like compounds having a thiophene ring instead of the phenylring are known from DE1941761. These known compounds differ from thestructures of formula I described in the present invention in that theyhave considerably smaller radicals R7 and R8 and in particular by thefact that R7 and R8 are not capable of forming a joint ring.

By these differences in the substituents R7 and R8, it is possible toeliminate the undesirable clonidine-like cardiovascular effectsdescribed above, which are mediated by the alpha-adrenoceptor action. Atthe same time, owing to these differences in the substituents, theNHE-inhibiting properties of the compounds described herein are enhancedto the micromolar and submicromolar range, whereas the compounds knownfrom DE1941761 show only extremely weak NHE-inhibiting effects, if any.

The present invention provides a different kind of NHE3 inhibitors.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide compounds offormula I

in which:

-   R¹ and R²    -   independently of one another are H, F, Cl, Br, I, CN, NO₂,        —(X)_(n)—C_(q)H_(2q)-Z, cycloalkyl having 3, 4, 5 or 6 carbon        atoms, alkenyl having 2, 3 or 4 carbon atoms, alkenylalkyl        having 3 or 4 carbon atoms, ethynyl or alkylalkynyl having 3 or        4 carbon atoms;    -   n is zero or 1;    -   X is oxygen, NH, N—CH₃, S(O)_(k);        -   k is zero, 1 or 2;    -   q is zero, 1, 2, 3, 4, 5 or 6;    -   Z is hydrogen or C_(m)F_(2m+1);        -   m is zero, 1, 2, 3 or 4;-   R³ is hydrogen, methyl, F, Cl, Br, I, CN, S(O)_(k)—CH₃, —NO₂,    —O—CH₃;    -   k is zero, 1 or 2;-   R4 is hydrogen, cycloalkyl having 3, 4, 5, or 6 carbon atoms,    alkenyl having 2, 3 or 4 carbon atoms, alkenylalkyl having 3 or 4    carbon atoms, ethynyl or alkylalkynyl having 3 or 4 carbon atoms,    —C_(r)H_(2r)—Y;    -   r is zero, 1, 2, 3 or 4;    -   Y is hydrogen or trifluoromethyl;-   R5 and R6 are hydrogen or together are a bond;-   R7 and R8    -   independently of one another are (C₃-C₅)-alkyl, (C₂-C₅)-alkenyl,        (C₂-C₅)-alkynyl, (C₃-C₆)-cycloalkyl or (C₄-C₆)-cycloalkenyl        or-   R7 and R8    -   together are an alkylene chain comprising 3 to 8 carbon atoms;        where none, some or all of their hydrogen atoms may be replaced        by fluorine atoms;        or-   R7 and R8    -   together are a radical

-   -   where R5 and R6 together form a bond;    -   R10 and R11        -   independently of one another are hydrogen, fluorine,            chlorine, bromine, methyl, CN, OH, —O—CH₃, NO₂, NH₂ or —CF₃;    -   R9 and R12        -   are hydrogen or F;    -   or    -   one of the substituents R9 and R12        -   is hydrogen;        -   and the other is F, Cl, Br, I, CN, NO₂, COOH, CO—NR13R14,            SO₂—NR13R14, alkenyl having 2, 3 or 4 carbon atoms,            alkenylalkyl having 3 or 4 carbon atoms, ethynyl,            alkylalkynyl having 3 or 4 carbon atoms or            —(X)_(n)—C_(q)H_(2q)-Z;        -   R13 and R14            -   are identical or different hydrogen or alkyl having 1,                2, 3 or 4 carbon atoms;        -   or        -   R13 and R14 together with the nitrogen to which they are            attached form a saturated 5-, 6- or 7-membered ring;        -   n is zero or 1;        -   X is oxygen, NH, N—CH₃, S(O)_(k);            -   k is zero, 1 or 2;        -   q is zero, 1, 2, 3, 4, 5 or 6;        -   and        -   Z is hydrogen or C_(m)F_(2m+1);            -   m is zero, 1, 2, 3 or 4;                and their pharmaceutically acceptable salts, and their                trifluoroacetic acid salts.

One embodiment relates to compounds of formula I in which

-   R1 and R2    -   independently of one another are H, F, Cl, Br, I, CN, NO₂,        —(X)_(n)—C_(q)H_(2q)-Z, cycloalkyl having 3, 4, 5 or 6 carbon        atoms, alkenyl having 2, 3 or 4 carbon atoms, alkenylalkyl        having 3 or 4 carbon atoms, ethynyl or alkylalkynyl having 3 or        4 carbon atoms;    -   n is zero or 1;    -   X is oxygen, NH, N—CH₃, S(O)_(k);        -   k is zero, 1 or 2;    -   q is zero, 1, 2, 3, 4, 5 or 6;    -   Z is hydrogen or C_(m)F_(2m+1);        -   m is zero, 1, 2, 3 or 4;-   R3 is hydrogen, methyl, F, Cl, Br, I, CN, S(O)_(k)—CH₃, —NO₂,    —O—CH₃;-   R4 is hydrogen, cycloalkyl having 3, 4, 5, or 6 carbon atoms,    alkenyl having 2, 3 or 4 carbon atoms, alkenylalkyl having 3 or 4    carbon atoms, ethynyl or alkylalkynyl having 3 or 4 carbon atoms,    —C_(q)H_(2q)-Z;    -   q is zero, 1, 2, 3 or 4;    -   Z is hydrogen or trifluoromethyl;-   R5 and R6    -   are hydrogen or together are a bond;-   R7 and R8    -   independently of one another are (C₃-C₅)-alkyl, (C₂-C₅)-alkenyl,        (C₂-C₅)-alkynyl, (C₃-C₆)-cycloalkyl or (C₄-C₆)-cycloalkenyl        or-   R7 and R8    -   together are an alkylene chain comprising 3 to 8 carbon atoms;        where none, some or all of their hydrogen atoms may be replaced        by fluorine atoms;        or-   R7 and R8    -   together are a radical

-   -   where R5 and R6 together form a bond;    -   R9, R10 and R11        -   independently of one another are hydrogen, fluorine,            chlorine, bromine, methyl, CN, OH, —O—CH₃, NO₂, NH₂ or —CF₃;    -   R9 and R12        -   are hydrogen;    -   or    -   one of the substituents R9 and R12        -   is hydrogen;        -   and the other is F, Cl, Br, I, CN, NO₂, COOH, CO—NR13R14,            SO₂—NR13R14, alkenyl having 2, 3 or 4 carbon atoms,            alkenylalkyl having 3 or 4 carbon atoms, ethynyl,            alkylalkynyl having 3 or 4 carbon atoms or            —(X)_(n)—C_(q)H_(2q)-Z;        -   R13 and R14            -   are identical or different hydrogen or alkyl having 1,                2, 3 or 4 carbon atoms;        -   n is zero or 1;        -   X is oxygen, NH, N—CH₃, S(O)_(k);            -   k is zero, 1 or 2;        -   q is zero, 1, 2, 3, 4, 5 or 6;        -   and        -   Z is hydrogen or C_(m)F_(2m+1);            -   m is zero, 1, 2, 3 or 4;                and their pharmaceutically acceptable salts, and their                trifluoroacetic acid salts.                Preference is given to compounds of formula I, in which:

-   R1 and R2    -   independently of one another are H, F, Cl, Br, CH₃, CF₃, SO₂CH₃,        SO₂NH₂;    -   but where at most one of the substituents R1 and R2 is hydrogen;

-   R3 is hydrogen, F or Cl;

-   R4 is hydrogen, alkyl having 1, 2, 3 or 4 carbon atoms, or    cyclopropyl;

-   R5 and R6    -   are hydrogen or together are a bond;

-   R7 and R8    -   together are an alkylene chain comprising 3, 4, 5, 6, 7 or 8        carbon atoms;        or

-   R7 and R8    -   together are a radical

-   -   where R5 and R6 together form a bond;    -   R10 and R11        -   independently of one another are hydrogen, OH, fluorine or            chlorine;    -   R9 and R12        -   are hydrogen;    -   or    -   one of the substituents R9 and R12        -   is hydrogen;        -   and the other is F, Cl, Br, CN, COOH, CO—NR13R14,            SO₂—NR13R14 or —(X)_(n)—C_(q)H_(2q)-Z;        -   R13 and R14            -   are identical or different hydrogen or methyl;        -   n is zero or 1;        -   X is oxygen, NH, N—CH₃ or S(O)_(k);            -   k is zero, 1 or 2;        -   q is zero, 1, 2, 3 or 4;        -   Z is hydrogen or CF₃;            and their pharmaceutically acceptable salts, and their            trifluoroacetic acid salts.

Particular preference is given to compounds of formula I in which:

-   R1 and R2    -   independently of one another are F, Cl, Br, CH₃ or CF₃;-   R3 is hydrogen;-   R4 is hydrogen, methyl, ethyl;-   R5 and R6    -   are hydrogen or together are a bond;-   R7 and R8    -   together are an alkylene chain comprising 3, 4, 5, 6, 7 or 8        carbon atoms;        or-   R7 and R8    -   together are a radical

-   -   where R5 and R6 together form a bond;    -   R10 and R11        -   independently of one another are hydrogen, OH or fluorine;    -   R9 and R12        -   are hydrogen;    -   or    -   one of the substituents R9 and R12        -   is hydrogen;        -   and the other is F, Cl, Br or —(X)_(n)—C_(q)H_(2q)-Z;        -   n is zero or 1;        -   X is oxygen, NH, N—CH₃ or S(O)_(k);            -   k is zero, 1 or 2;        -   q is zero or 1;        -   Z is hydrogen or CF₃;            and their pharmaceutically acceptable salts, and their            trifluoroacetic acid salts.

Very particular preference is given to the following compounds offormula I, selected from the group consisting of:

-   trans-R,R-2-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylamine,-   trans-R,R-2-bromo-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylamine,-   2-chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine,-   2-bromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine,-   2-chloro-3N-(4-methyl-2-benzimidazolyl)-4-methyl-3-thienylamine,-   2-chloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine,-   2-chloro-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophene,-   2-bromo-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophene,-   2-bromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene,-   2-chloro-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene,-   2-chloro-3N-(4-hydroxy-2-benzimidazolylamino)-4-methylthiophene,-   (1H-benzimidazol-2-yl)-(2-chloro-4-methylthiophen-3-yl)-methylamine,-   (2-bromo-4-methylthiophen-3-yl)-(5-fluoro-1H-benzimidazol-2-yl)-amine,-   2,4-dichloro-3N-(2-benzimidazolylamino)thiophen,    2-bromo-4-chloro-3N-(2-benzimidazolylamino)thiophen,-   2,4-dichloro-3N-(4-methyl-2-benzimidazolyl-amino)thiophen,    trans-R,R-2,4-Dichlor-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamin,-   2,4-dichloro-3N-(4-chlor-2-benzimidazolyl-amino)thiophen    and-   2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene    and their pharmaceutically acceptable salts, for example the    hydrochloride or the hydrobromide or the methanesulfonate of each of    the compounds.

The compounds of formula I can be present in the form of their salts.Suitable acid addition salts are salts of all pharmacologicallyacceptable acids, for example halides, in particular hydrochlorides,hydrobromides, lactates, sulfates, citrates, tartrates, acetates,phosphates, methylsulfonates, benzenesulfonates, p-toluenesulfonates,adipinates, fumarates, gluconates, glutamates, glycerolphosphates,maleates, benzoates, oxalates and pamoates. This group also correspondsto the physiologically acceptable anions; but also trifluoroacetates.

If the compounds contain an acid group, they are capable of formingsalts with bases, for example as alkali metal salts, preferably sodiumor potassium salts, or as ammonium salts, for example as salts withammonia or organic amines or amino acids. They can also be present aszwitterion.

If the compounds of formula I contain one or more centers of asymmetry,the compounds can independently be both S- and R-configured. Thecompounds can be present as optical isomers, as diastereomers, asracemates or as mixtures thereof.

The compounds of formula I can furthermore be present as tautomers or asa mixture of tautomeric structures. This refers, for example, to thefollowing tautomers:

Alkyl radicals can be straight-chain or branched. This also applies whenthey carry substituents or are present as substituents of otherradicals, for example in fluoroalkyl radicals or alkoxy radicals.Examples of alkyl radicals are methyl, ethyl, n-propyl, isopropyl(=1-methylethyl), n-butyl, isobutyl (=2-methylpropyl), sec-butyl(=1-methyl-propyl), tert-butyl (=1,1-dimethylethyl), n-pentyl,isopentyl, tert-pentyl, neopentyl or hexyl. Preferred alkyl radicals aremethyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl,n-hexyl. In alkyl radicals, one or more, for example 1, 2, 3, 4, 5, 6,7, 8 or 9, hydrogen atoms may be substituted by fluorine atoms. Examplesof such fluoroalkyl radicals are trifluoromethyl, 2,2,2-trifluoroethyl,pentafluoroethyl, heptafluoroisopropyl. Substituted alkyl radicals maybe substituted in any positions.

Alkenyl radicals may be straight-chain or branched. This also applieswhen they are present as substituents, for example in alkenylalkylene.The alkenyl radicals can be unsaturated in different positions. Examplesof alkenyl radicals are ethenyl, propenyl or butenyl.

Alkynyl radicals can be straight-chain or branched. This also applieswhen they are present as substituents, for example in alkynylalkylene.The alkynyl radicals can be unsaturated in different positions. Examplesof alkynyl radicals are ethynyl, propynyl or butynyl.

Examples of cycloalkyl radicals are cyclopropyl, cyclobutyl, cyclopentylor cyclohexyl. Substituted cycloalkyl radicals can be substituted in anypositions. The cycloalkyl radicals may also be present branched asalkylcycloalkyl or cycloalkylalkyl.

Also described are methods for preparing compounds according to theinvention. Thus, the substances described by formula I can be preparedin a manner known to the person skilled in the art from theisothiocyanate II parent compounds and the appropriate diamines III.

The thiourea derivative which is formed as an intermediate is cyclizedusing methyliodide (Synthesis, 1974, 41-42) or carbodiimide (Synthesis,1977, 864-865) or using p-toluenesulfonyl chloride to give thecorresponding compound of formula I. If the isothiocyanates II employedhere are not commercially available, they can be prepared in a mannerknown from the literature from the corresponding aminothiophenederivatives, using methods known to the person skilled in the art, forexample by treatment with thiophosgene (J. Med. Chem., 1975, 18, 90-99)or thiocarbonyl diimidazole (Justus Liebigs Ann. Chem., 1962, 657, 104).

In addition to the isothiocyanates II described above, it is alsopossible to successfully react the isocyanates IV

with amines of the type of formula III to give the compounds of formulaI. Here, the urea derivative which is formed as an intermediate iscyclized using phosphorus oxychloride to give the correspondingcompounds of formula I.

In the present invention, it was surprisingly possible to demonstratethat the compounds described are potent inhibitors of the sodium/protonexchanger (NHE), in particular the sodium/proton exchanger of subtype 3(NHE3).

Owing to the NHE-inhibitory properties, the compounds of formula I aresuitable for the prevention and treatment of diseases caused by anactivation of NHE or by an activated NHE, and of diseases which aresequelae of damage caused by NHE.

Since NHE inhibitors act predominantly via influencing cellular pHregulation, they can be combined in a favorable manner with othercompounds which also regulate the intracellular pH, suitable combinationpartners being inhibitors of the enzyme group of the carbonatedehydratases, inhibitors of the bicarbonate-ion-transporting systems,such as the sodium bicarbonate cotransporter (NBC) or thesodium-dependent chloride/bicarbonate exchanger (NCBE), and also NHEinhibitors having inhibitory action on other NHE subtypes, since theycan modulate or enhance the pharmacologically relevant pH-regulatingeffects of the NHE inhibitors described herein.

The use of the compounds according to the invention relates to theprevention and treatment of acute and chronic diseases in veterinary andhuman medicine.

The pharmacological action of the compounds of formula I ischaracterized in that they induce an improvement in the respiratorydrive and can therefore be used in the treatment of disturbedrespiratory conditions for example in the following clinical conditionsand diseases: disturbed central respiratory drive (e.g. central sleepapnea, sudden infant death, postoperative hypoxia), muscular-relatedrespiratory disorders, respiratory disorders after long-termventilation, respiratory disorders during adaptation in a high mountainarea, obstructive and mixed forms of sleep apnea, acute and chronic lungdiseases with hypoxia and hypercapnia.

The compounds additionally increase the muscle tone of the upperairways, so that snoring is suppressed. As a result, the compoundsmentioned are advantageously used for preparing a medicament for theprevention and treatment of sleep apnea and muscular-related respiratorydisturbances and for preparing a medicament for the prevention andtreatment of snoring.

A combination of an NHE inhibitor of formula I with a carboanhydraseinhibitor (e.g. acetazolamide) can be advantageous, the latter producingmetabolic acidosis and thereby already increasing respiratory activity,may prove to be advantageous as a result of increased action anddecreased use of active compound.

Owing to their NHE3-inhibitory action, the compounds according to theinvention spare cellular energy resources which, during toxic andpathogenic events, are rapidly depleted, thus resulting in cell damageor cell death. Here, the high-energy ATP-consuming resorption of sodiumin the proximal tubulus is, under the influence of the compounds offormula I, temporarily switched off, and the cell is thus able tosurvive an acute pathogenic, ischemic or toxic situation. The compoundsare therefore suitable by way of example for use as drugs for treatingischemic noxa, for example acute kidney failure.

Furthermore, the compounds are also suitable for treating all chronicrenal disorders and forms of nephritis which, as a consequence ofincreased elimination of protein, result in chronic kidney failure.Accordingly, the compounds of formula I are suitable for preparing amedicament for the treatment of diabetic late damage, diabeticnephropathy and chronic renal disorders, in particular all inflammationsof the kidney (nephritides) associated with increased elimination ofprotein/albumin.

It has been shown that the compounds used according to the inventionhave mild laxative action and, accordingly, can also be usedadvantageously as laxatives or for the prophylaxis of intestinalobstruction.

Furthermore, the compounds according to the invention can be usedadvantageously for the prevention and therapy of acute and chronicdisorders of the intestinal tract triggered, for example, by ischemicstates in the intestinal region and/or by subsequent reperfusion or bystates and events of inflammation. Such complications can occur, forexample, by lack of intestinal peristalsis, as is frequently observed,for example, after surgical interventions, in the case of bowelobstruction or in cases of strongly reduced intestinal motility.

Using the compounds according to the invention, it is possible toprevent gallstone formation.

The NHE inhibitors according to the invention are generally suitable fortreating diseases caused by ischemia and by reperfusion.

As a result of their pharmacological properties, the compounds accordingto the invention are suitable for use as antiarrhythmics.

Owing to their cardioprotective component, the NHE inhibitors of formulaI are highly suitable for infarct prophylaxis and infarct treatment andfor treatment of angina pectoris, and they also inhibit, or stronglyreduce, in a preventative manner, the pathophysiological processes whichcontribute to ischemically induced damage, in particular those whichtrigger ischemically induced cardiac arrhythmias. Owing to theirprotective action against pathological hypoxic and ischemic situations,the compounds of formula I used according to the invention can, asinhibitors of the cellular Na⁺/H⁺ exchange mechanism, be used asmedicaments for treating all acute or chronic damage caused by ischemia,or diseases induced primarily or secondarily by this damage.

This relates to their use as medicaments for surgical interventions.Thus, the compounds according to the invention can be used for organtransplantations, where the compounds can be used both for protectingthe organs in the donor before and during removal, for protecting organsthat have been removed, for example during treatment with or storage inphysiological bath fluids, and also during transfer into the recipientorganism pretreated with compounds of formula I.

The compounds are also useful medicaments with protective action duringangioplastic surgical interventions, for example on the heart, but alsoin peripheral organs and vessels.

Since NHE inhibitors protect human tissue and organs not onlyeffectively against damage caused by ischemia and reperfusion but alsoagainst the cytotoxic action of medicaments used in particular in cancertherapy and the therapy of autoimmune diseases, the combinedadministration with compounds of formula I is suitable for suppressingor reducing the cytotoxic effects of a therapy. By reducing thecytotoxic effects, in particular cardiotoxicity, by comedication withNHE inhibitors it is furthermore possible to increase the dose of thecytotoxic therapeutics and/or to prolong medication with suchmedicaments. The therapeutic benefit of such a cytotoxic therapy can beenhanced considerably by combination with NHE inhibitors.

The compounds of formula I are suitable in particular for improving thetherapy with medicaments having an undesirable cardiotoxic component.

Owing to their protective action against ischemically induced damage,the compounds according to the invention are also suitable for use asmedicaments for treating ischemias of the nervous system, in particularthe central nervous system, where they can be used, for example, fortreating stroke or cerebral edema.

The compounds of formula I are also suitable for the therapy andprophylaxis of diseases and disorders induced by overexcitability of thecentral nervous system, in particular for the treatment of epilepticdisorders, centrally induced clonic and tonic spasms, states ofpsychological depression, anxiety disorders and psychoses. Here, the NHEinhibitors according to the invention can be used on their own or incombination with other substances having antiepileptic action or withantipsychotic active compounds, or carbonate dehydratase inhibitors, forexample acetazolamide, and also with other inhibitors of NHE or of thesodium-dependent chloride/bicarbonate exchanger (NCBE).

In addition, the compounds of formula I according to the invention arealso suitable for treating types of shock, such as, for example, ofallergic, cardiogenic, hypovolemic and bacterial shock.

The compounds of formula I can also be used for the prevention andtreatment of thrombotic disorders since, as NHE inhibitors, they arealso capable of inhibiting platelet aggregation themselves. In addition,they can prevent or inhibit excessive release of mediators ofinflammation and coagulation, in particular of the von Willebrand factorand thrombogenic selecting proteins which takes place following ischemiaand reperfusion. It is thus possible to reduce and eliminate thepathogenic effect of significant thrombogenic factors. Accordingly, theNHE inhibitors of the present invention can be combined with othercompounds having anticoagulative and/or thrombolytic action, such as,for example, recombinant or natural tissue plasminogen activator,streptokinase, urokinase, acetylsalicylic acid, thrombin antagonists,factor Xa antagonists, medicaments with fibrinolytic action, thromboxanereceptor antagonists, phosphodiesterase inhibitors, factor VIIaantagonists, clopidogrel, ticlopidine, etc. Combined use of the presentNHE inhibitors with NCBE inhibitors and/or with inhibitors of carbonatedehydratase, such as, for example, with acetazolamide, is particularlybeneficial.

Furthermore, the compounds of formula I according to the invention havestrong inhibiting action on cell proliferation, for example onfibroblast cell proliferation and proliferation of smooth vascularmuscle cells. The compounds of formula I are therefore usefultherapeutics for diseases in which cell proliferation is a primary orsecondary cause and can therefore be used as antiatherosclerotics, asagents against chronic kidney failure and against neoplastic diseases.Thus, they can be used for treating organ hypertrophy and hyperplasia,for example of the heart and the prostate. Compounds of formula I aretherefore suitable for the prevention and treatment of cardiacinsufficiency (congestive heart failure=CHF) and for the treatment andprevention of prostate hyperplasia and prostate hypertrophy.

The compounds of formula I furthermore delay or prevent fibroticdisorders. Thus, they are excellent agents for treating fibroses of theheart, and also pulmonary fibrosis, liver fibrosis, kidney fibrosis andother fibrotic disorders.

Since there is significant elevation of NHE in essential hypertensives,the compounds of formula I are suitable for the prevention and treatmentof high blood pressure and of cardiovascular disorders.

Here, they can be used for the treatment of high blood pressure and ofcardiovascular disorders on their own or with a suitable combination andformulation cocomponent. Thus, it is possible, for example, to combineone or more diuretics having thiazide-like action, loop diuretics,aldosterone and pseudoaldosterone antagonists, such ashydrochlorothiazide, indapamide, polythiazide, furosemide, piretanide,torasemide, bumetanide, amiloride, triamterene, spironolactone oreplerone, with compounds of formula I. Furthermore, the NHE inhibitorsof the present invention can be used in combination with calciumantagonists such as verapamil, diltiazem, amlodipine or nifedipine, andalso with ACE inhibitors, such as, for example, ramipril, enalapril,lisinopril, fosinopril or captopril. Further favorable combinationpartners include beta-blockers such as metoprolol, albuterol etc.,antagonists of the angiotensin receptor and its receptor subtypes, suchas losartan, irbesartan, valsartan, omapatrilat, gemopatrilat,endothelin antagonists, renin inhibitors, adenosine receptor agonists,inhibitors and activators of calcium channels, such as glibenclamide,glimepiride, diazoxide, cromakalim, minoxidil and its derivatives,activators of the mitochondrial ATP-sensitive potassium channel(mitoK(ATP) channel), inhibitors of other potassium channels, such asinhibitors of Kv1.5 etc.

Owing to their antiphlogistic action, the NHE inhibitors can be used asantiinflammatory agents. Mechanistically interesting is the inhibitionof the release of mediators of inflammation. Thus, the compounds can beused alone or in combination with an antiphlogistic agent for theprevention or treatment of chronic and acute inflammatory disorders. Thecombination partners used are advantageously steroidal and non-steroidalantiinflammatory agents.

Moreover, it has been found that compounds of formula I exert abeneficial influence on serum lipoproteins. They can therefore be usedfor the prophylaxis and regression of atherosclerotic changes byexcluding a causal risk factor. This includes not only primaryhyperlipidemias but also certain secondary hyperlipidemias as areencountered, for example, in diabetes. Additionally, the compounds offormula I reduce infarcts induced by metabolic anomalies considerablyand, in particular, lead to a significant reduction in the size andseverity of the infarct induced.

Accordingly, the compounds mentioned are used advantageously forpreparing a medicament for the treatment of hypercholesterolemia, forpreparing a medicament for the prevention of atherogenesis, forpreparing a medicament for the prevention and treatment ofatherosclerosis, for preparing a medicament for the prevention andtreatment of diseases induced by elevated cholesterol levels, forpreparing a medicament for the prevention and treatment of diseasesinduced by endothelial dysfunction, for preparing a medicament for theprevention and treatment of hypertension induced by atherosclerosis, forpreparing a medicament for the prevention and treatment of thrombosesinduced by atherosclerosis, for preparing a medicament for theprevention and treatment of ischemic damage and post-ischemicreperfusion damage induced by hypercholesterolemia and endothelialdysfunction, for preparing a medicament for the prevention and treatmentof cardiac hypertrophies and cardiomyopathies and congestive heartfailure (CHF), for preparing a medicament for the prevention andtreatment of coronary vascospasms and myocardial infarcts induced byhypercholesterolemia and endothelial dysfunction, for preparing amedicament for the treatment of the conditions mentioned in combinationwith hypotensive substances, preferably with angiotensin convertingenzyme (ACE) inhibitors and angiotensin receptor antagonists. Acombination of an NHE inhibitor of formula I with an active compoundthat lowers the lipid concentration in the blood, preferably an HMG-CoAreductase inhibitor (for example lovastatin or pravastatin), the latterhaving hypolipidemic action, thereby enhancing the hypolipidemicproperties of the NHE inhibitor of formula I, has been found to be afavorable combination with increased action and reduced use of activecompound.

Thus, compounds of formula I bring about effective protection againstendothelial damage of various origins. Owing to this protection of thevessels against the syndrome of endothelial dysfunction, compounds offormula I are useful medicaments for the prevention and treatment ofcoronary vascospasms, peripheral vascular diseases, in particularintermittent claudication, of atherogenesis and atherosclerosis, ofleft-ventricular hypertrophy and of dilated cardiomyopathy, and ofthrombotic disorders.

Moreover, NHE inhibitors of formula I are suitable for treatingnon-insulin-dependent diabetes (NIDDM) where for example insulinresistance is suppressed. Here, to enhance antidiabetic efficacy andquality of action of the compounds according to the invention, it may befavorable to combine these compounds with a biguanide such as metformin,with an antidiabetic sulfonylurea, such as glyburide, glimepiride,tolbutamide, etc., a glucosidase inhibitor, a PPAR agonist, such asrosiglitazone, pioglitazone, etc., with an insulin product in adifferent administration form, with a DB4 inhibitor, with an insulinsensitizer or with meglitinide.

In addition to the acute antidiabetic effects, the compounds of formulaI counteract the development of late complications of diabetes, and theycan therefore be used as medicaments for the prevention and treatment ofdiabetic late damage, such as diabetic nephropathy, diabetic neuropathy,diabetic retinopathy, diabetic cardiomyopathy and other disorders whichoccur as a result of diabetes. In this connection, they can be combinedadvantageously with the antidiabetic medicaments described above underthe NIDDM treatment. A combination with a favorable administration formof insulin may be of particular importance.

In addition to the protective effects against acute ischemic events andsubsequent likewise acute reperfusion events, the NHE inhibitors offormula I according to the invention also have direct therapeuticallyuseful action against disorders and impairments of the entire mammalianorganism which are associated with manifestations of the chronicallyprogressing aging process and can also be independent of acute states ofhypoperfusion, also occurring under normal, non-ischemic conditions.These pathological age-related manifestations, such as disease, illnessand death, induced over the long time of aging, which are now accessibleto treatment with NHE inhibitors, are disorders and disturbances causedto a substantial extent by age-related changes in vital organs and theirfunction which become more and more important in the aging organism.

Disorders associated with age-related dysfunction and age-relatedsymptoms of wear of organs are, for example, inadequate responsivenessand reactivity of the blood vessels to contraction and relaxationreactions. This age-related decline in vascular reactivity toconstricting and relaxing stimuli, which are an essential process of thecardiovascular system and thus of life and health, can be significantlydiminished or abolished by NHE inhibitors. An important function and ameasure of the maintenance of vascular reactivity is the blocking orslowing of the age-related progression of endothelial dysfunction, whichcan be abolished highly significantly by NHE inhibitors. The compoundsof formula I are thus outstandingly suitable for the treatment andprevention of the age-related progression of endothelial dysfunction,especially of intermittent claudication. Moreover, the compounds offormula I are thus outstandingly suitable for the treatment andprevention of cardiac insufficiency, of congestive heart failure (CHF),and for the treatment and in particular for the prevention ofage-related types of cancer.

Consideration may likewise be given to combination with hypotensivemedicaments, such as with ACE inhibitors, angiotensin receptorantagonists, diuretics, Ca²⁺ antagonists, etc., or withmetabolism-normalizing medicaments, such as cholesterol-lowering agents.The compounds of formula I are thus suitable for the prevention ofage-related tissue changes and for prolonging life while maintaining ahigh quality of life.

The compounds of the invention are effective inhibitors of the cellularsodium/proton antiporter (Na/H exchanger) which, in numerous disorders(essential hypertension, atherosclerosis, diabetes, etc.), is alsoelevated in cells which are easily amenable to measurements, such as,for example, in erythrocytes, platelets or leukocytes. The compoundsused according to the invention are therefore suitable as excellent andsimple scientific tools, for example in their use as diagnostic aids forthe determination and differentiation of particular types ofhypertension, but also of atherosclerosis, of diabetes and of latecomplications of diabetes, of proliferative disorders, etc.

NHE3 inhibitors are furthermore suitable for treating disorders (humanand veterinary) caused by bacteria and by protozoa. In the case ofdisorders caused by protozoa, particular mention may be made of malariadiseases of man and of coccidiosis in poultry.

Moreover, the compounds are suitable as agents for controlling suckingparasites in human and veterinary medicine and in crop protection. Here,the use as an agent against blood-sucking parasites in human andveterinary medicine is preferred.

The compounds of the formula I are characterised apart from their potentNHE inhibition values, their pharmacological properties and the absenceof unwanted biological effects also by favorable pharmacokineticproperties, which let their use as medicaments appear particularlyfavorable.

The invention thus relates to medicaments for human, veterinary orphytoprotective use which comprise an effective amount of a compound offormula I and/or a pharmaceutically acceptable salt thereof alone or incombination with other pharmacologically active compounds ormedicaments.

Medicaments comprising a compound I can be administered, for example,orally, parenterally, intramuscularly, intravenously, rectally, nasally,by inhalation, subcutaneously or by suitable transcutaneouslyadministration with the preferred administration being dependent on theparticular appearance of the disorder. Here, the compounds I can be usedalone or together with pharmaceutical excipients, both in veterinarymedicine and in human medicine and in crop protection.

Excipients suitable for the desired pharmaceutical formulation arefamiliar to the skilled worker on the basis of his expert knowledge.Besides solvents, gel formers, suppository bases, tablet excipients andother active ingredient carriers, it is possible to use, for example,antioxidants, dispersants, emulsifiers, antifoams, masking flavors,preservatives, solubilizers or colorants.

For a form for oral use, the active compounds are mixed with theadditives suitable for this purpose, such as carriers, stabilizers orinert diluents, and converted by conventional methods into suitabledosage forms such as tablets, coated tablets, two-piece capsules,aqueous, alcoholic or oily solutions. Examples of inert carriers whichcan be used are gum arabic, magnesia, magnesium carbonate, potassiumphosphate, lactose, glucose or starch, especially corn starch.Preparation can moreover take place both as dry and as wet granules.Examples of suitable oily carriers or solvents are vegetable or animaloils such as sunflower oil or fish liver oil.

For subcutaneous, percutaneous or intravenous administration, the activecompounds used are converted into a solution, suspension or emulsion, ifdesired with the substances customary for this purpose, such assolubilizers, emulsifiers or other excipients. Examples of suitablesolvents are: water, physiological saline or alcohols, for exampleethanol, propanol, glycerol, and also sugar solutions, such as glucoseor mannitol solutions, or else a mixture of the various solventsmentioned.

Suitable as pharmaceutical formulation for administration in the form ofaerosols or sprays are, for example, solutions, suspensions or emulsionsof the active compound of formula I in a pharmaceutically acceptablesolvent, such as, in particular, ethanol or water, or a mixture of suchsolvents.

The formulation may, if required, also comprise other pharmaceuticalexcipients such as surfactants, emulsifiers and stabilizers, and apropellant gas. Such a preparation normally contains the active compoundin a concentration of about 0.1 to 10, in particular of about 0.3 to 3%by weight.

The dosage of the active compound of formula I to be administered andthe frequency of administration depend on the potency and duration ofaction of the compounds used; also on the nature and severity of thedisease to be treated, and on the sex, age, weight and individualresponse of the mammal to be treated.

On average, the daily dose of the compound of formula I for a patientweighing about 75 kg is at least 0.001 mg/kg, preferably 0.1 mg/kg, upto a maximum of 30 mg/kg, preferably 1 mg/kg, of body weight. For acutesituations, for example immediately after suffering apnea in highmountain regions, it may even be necessary for the dosages to be higher.Especially on i.v. use, for example for an infarct patient in anintensive care unit, up to 200 mg/kg per day may be necessary. The dailydose can be divided into one or more, for example up to 4, individualdoses.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of this disclosure. For a better understanding of the invention,its operating advantages, and specific objects attained by its use,reference should be made to the following description in which there areillustrated and described preferred embodiments of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

For the purpose of describing the specific compounds of the presentinvention, it is understood that if the compounds are enantiomericallypure, the configuration and/or the sign of the optical rotation isgiven, and if these data are missing, the compounds are racemates or notoptically active.

The retention times (Rt) given below refer to LCMS measurements with thefollowing parameters:

Analytical Methods:

A stationary phase: Merck Purospher 3μ 2 × 55 mm mobile phase: 95% H₂O(0.1% HCOOH) → 95% acetonitrile (0.1% HCOOH); 5 min → 95% acetonitrile(0.1% HCOOH); 2 min → 95% H₂O (0.1% HCOOH); 1 min; 0.45 ml/min. Bstationary phase: YMC J'sphere H80 ~4μ 2.1 × 33 mm mobile phase: 95% H₂O(0.1% HCOOH) → 95% acetonitrile (0.08% HCOOH); 2.5 min → 95%acetonitrile (0.08% HCOOH); 0.5 min → 95% H₂O (0.1% HCOOH); 0.5 min; 1.3ml/min. C stationary phase: YMC J'sphere H80 2 × 33 mm, 4μ, 2.1 × 20 mmmobile phase: 90% H₂O (0.05% TFA) → 95% acetonitrile; 1.9 min; → 95%acetonitrile 0.5 min; 1 ml/min. D stationary phase: Merck Purospher 3μ 2× 55 mm mobile phase: 95% H₂O (0.1% HCOOH)→ 95% acetonitrile (0.1%HCOOH); 3.4 min → 95% acetonitrile (0.1% HCOOH); 1 min → 95% H₂O (0.1%HCOOH); 0.2 min; 0.75 ml/min. E stationary phase: Merck Purospher 3μ 2 ×55 mm mobile phase: 95% H₂O (0.05% CF3COOH)→ 95% acetonitrile (0.05%CF3COOH); 3.4 min → 95% acetonitrile (0.05% CF3COOH); 1 min; 0.75ml/min. F stationary phase: YMC J'sphere H80, 4μ, 2.1 × 20 mm mobilephase: 96% H₂O (0.05% CF3COOH) → 95% acetonitrile; 2 min; → 95%acetonitrile 0.4 min; 1 ml/min. Preparative HPLC was carried out underthe following conditions: stationary phase: Merck Purospher RP18 (10 μM)250 × 25 mm mobile phase: 90% H₂O (0.05% TFA)→ 90% acetonitrile; 40 min;25 ml/min

EXAMPLE 1 3N-(5-Fluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

-   a) 4-Methyl-3-thienyl isothiocyanate    is obtained by reacting equimolar amounts of    3-amino-4-methylthiophene and N,N′-thiocarbonyldiimidazole in    anhydrous tetrahydrofuran (THF) by stirring the reaction mixture at    room temperature for 5 hours and then allowing the mixture to stand    at room temperature overnight. 4-Methyl-3-thienyl isothiocyanate is    isolated by distillative removal of the solvent under reduced    pressure using a rotary evaporator, dissolving the residue in ethyl    acetate and washing the organic phase repeatedly with water. The    organic phase is dried over sodium sulfate and the organic solvent    is then distilled off under reduced pressure using a rotary    evaporator, giving 4-methyl-3-thienyl isothiocyanate as a brown oily    residue. 4-Methyl-3-thienyl isothiocyanate can be used without    further purification.-   b) N-(2-Amino-5-fluorophenyl)-N′-(4-methyl-3-thienyl)thiourea

0.02 mol of 4-fluoro-1,2-diaminobenzene is added to a solution of 0.02mol of 4-methyl-3-thienyl isothiocyanate in 60 ml of anhydrous THF. Thereaction mixture is stirred at room temperature for 2 hours and thenallowed to stand overnight, and the solvent is then distilled off underreduced pressure using a rotary evaporator and the oily residue ispurified on a silica gel column using a mixture of identical proportionsof toluene and ethyl acetate.

Brown crystalline solid. M.p. 180° C.

-   c) 3N-(5-Fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride

A molar excess (about 1.5 to 4 mol) of methyl iodide is added to 1.5 g(0.0053 mol) ofN-(2-amino-5-fluorophenyl)-N′-(4-methyl-3-thienyl)thiourea in 50 ml ofanhydrous ethanol, and the mixture is boiled at reflux for 5 hours. Themixture is allowed to stand at room temperature overnight and theethanol is then distilled off under reduced pressure using a rotaryevaporator, water is added to the residue and the pH is adjusted to 8-9using saturated aqueous sodium bicarbonate solution. The mixture isextracted repeatedly with ethyl acetate, the organic phase is washedwith water and dried over sodium sulfate, the solvent is distilled offunder reduced pressure using a rotary evaporator and the residue ispurified by silica gel column chromatography using a solvent mixture ofidentical proportions of ethyl acetate and toluene (hereinbelow referredto as “mixture 2”) as mobile phase. The oily product obtained afterdistillative removal of the organic solvent is dissolved in ethylacetate and made highly acidic using a saturated solution of hydrogenchloride in dry diethyl ether, and the precipitate that crystallizes outis, after relatively long standing, filtered off. Crystalline solid,m.p. 192+/−2° C.

EXAMPLE 22-Chloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride and2,5-dichloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

A solution of 0.24 g (0.0018 mol) of N-chlorosuccinimide in 15 ml ofglacial acetic acid is added dropwise to a solution of 0.5 g (0.0018mol) of 3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride in 25 ml of glacial acetic acid, the reaction mixture isstirred at room temperature for about 2 to 3 hours and the solvent isdistilled off under reduced pressure using a rotary evaporator. Water isadded to the residue and the mixture is then made alkaline using 2N NaOHand extracted with ethyl acetate, the organic phase is washed with waterand dried over sodium sulfate and the solvent is distilled off underreduced pressure using a rotary evaporator. The resulting oily residueis, by medium pressure column chromatography, using a solvent mixture of20 parts of ethyl acetate, 10 parts of n-heptane and 3 parts of glacialacetic acid (hereinbelow referred to as “mixture 17”) as mobile phase,separated and treatment with a solution of hydrogen chloride gas gives:

2-chloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride from fraction 1 and 2: colorless to slightly yellowishcrystalline product, m.p. 200-202° C.,2,5-dichloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride from fraction 3: colorless to slightly yellowishcrystalline product, m.p. 286-288° C.

EXAMPLE 3 3N-(5,6-Dichloro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

-   a) N-(2-Amino-4,5-dichlorophenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and    4,5-dichloro-1,2-diaminobenzene. Crystalline solid, m.p. 310-320° C.-   b) 3N-(5,6-Dichloro-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride    is obtained analogously to the procedure described in example 1c)    from N-(2-amino-4,5-dichlorophenyl)-N′-(4-methyl-3-thienyl)thiourea    and methyl iodide.

Crystalline solid, m.p. 290-294° C.

EXAMPLE 4 3N-(2-Benzimidazolyl)-4-methyl-3-thienylamine hydrochloride

-   a) N-(2-Aminophenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and 1,2-diaminobenzene.    Crystalline solid having a 1st m.p. of 177-182° C., followed by    another crystallization and 2nd m.p. 285-290° C.-   b) 3N-(2-Benzimidazolyl)-4-methyl-3-thienylamine hydrochloride    is obtained analogously to the procedure described in example 1c)    from N-(2-aminophenyl)-N′-(4-methyl-3-thienyl)thiourea and methyl    iodide.

Crystalline solid following recrystallization from ethylacetate/ethanol, m.p. 194-200° C.

EXAMPLE 5 3N-(-4-Fluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

-   a) 3-Fluoro-1,2-diaminobenzene    is obtained as an oily amorphous product by hydrogenation of    3-fluoro-2-nitrophenyl hydrazine (prepared by reaction of    2,6-difluoronitrobenzene with hydrazine hydrate) using hydrogen and    10% palladium on carbon catalyst in methanol at room temperature and    atmospheric pressure.-   b) N-(2-Amino-3-fluorophenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and    3-fluoro-1,2-diaminobenzene. Crystalline solid, point of    decomposition>240° C.-   c) 3N-(-4-Fluoro-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride    is obtained analogously to the procedure described in example 1c)    from N-(2-amino-3-fluorophenyl)-N′-(4-methyl-3-thienyl)thiourea and    methyl iodide. Amorphous precipitate which crystallizes under    acetone. Crystalline solid, m.p. 220-230° C.

EXAMPLE 6 3N-(4,6-Difluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

-   a) N-(2-Amino-3,5-difluorophenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and    3,5-difluoro-1,2-diaminobenzene. Crystalline solid, 1st melting    point: 178-182° C., another crystallization with 2nd m.p.: 299-301°    C.-   b) 3N-(4,6-Difluoro-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride    is obtained analogously to the procedure described in example 1c)    from N-(2-amino-3,5-difluorophenyl)-N′-(4-methyl-3-thienyl)thiourea    and methyl iodide. Amorphous precipitate which crystallizes under    ethyl acetate. Crystalline solid, m.p. 232-234° C.

EXAMPLE 73N-(4,5,6,7-Tetrafluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

-   a)    N-(2-Amino-3,4,5,6-tetrafluorophenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and    3,4,5,6-tetrafluoro-1,2-diaminobenzene. Crystalline solid, m.p.:    286-290° C.-   b) 3N-(3,4,5,6-Tetrafluoro-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride    is obtained analogously to the procedure described in example 1c)    from    N-(2-amino-3,4,5,6-tetrafluorophenyl)-N′-(4-methyl-3-thienyl)thiourea    and methyl iodide. Amorphous precipitate which crystallizes under    ethyl acetate. Crystalline solid, m.p. 225-228° C.

EXAMPLE 8 3N-(4-Methyl-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

-   a) N-(2-Amino-3-methylphenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and    3-methyl-1,2-diaminobenzene. Crystalline solid, m.p. 184-186° C.,-   b) 3N-(4-Methyl-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride    is obtained analogously to the procedure described in example 1c)    from N-(2-amino-3-methylphenyl)-N′-(4-methyl-3-thienyl)thiourea and    methyl iodide. Amorphous precipitate which crystallizes under    acetone. Crystalline solid, point of decomposition: 320° C.

EXAMPLE 9trans-3N-(3a,4,5,6,7,7a-Hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride (racemate)

-   a) trans-N-(2-Aminocyclohexyl)-N′-(4-methyl-3-thienyl)thiourea    (racemate)    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and racemic    trans-1,2-diaminocyclohexane. Crystalline solid, m.p. 205-210° C.,-   b)    trans-3N-(3a,4,5,6,7,7a-Hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride (racemate)    0.6 g of racemic    trans-N-(2-aminocyclohexyl)-N′-(4-methyl-3-thienyl)thiourea is    suspended in 60 ml of toluene and dissolved by heating at 90° C. The    mixture is allowed to cool to 70° C., a solution of 0.376 g of    dicyclohexylcarbodiimide in 5 ml of anhydrous toluene is added    dropwise and the mixture is stirred for a total of about 10 hours at    70° C. and for 2-3 days at room temperature. The crystalline solid    is filtered off, the solvent is removed under reduced pressure using    a rotary evaporator and the resulting oily residue is dissolved in a    little ethyl acetate. Following addition of an anhydrous solution of    hydrogen chloride in diethyl ether, a viscous precipitate is formed    which, after addition of a little ethanol, crystallizes. Crystalline    solid, m.p.: 261-264° C.

EXAMPLE 10trans-R,R-3N-(3a,4,5,6,7,7a-Hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

-   a) trans-R,R—N-(2-Aminocyclohexyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and    trans-R,R-1,2-diaminocyclohexane by separation by silica gel column    chromatography, eluting with a solvent mixture consisting of 10    parts of ethyl acetate, 5 parts of n-heptane, 5 parts of methylene    chloride, 5 parts of methanol and 1 part of 26% strength aqueous    ammonia (hereinbelow referred to as “mixture 4”), as an amorphous    oily product in addition to a crystalline product having a higher    molecular weight of m.p. 94-100° C.

The amorphous product is processed further without further purification.

-   b)    trans-R,R—N-(3a,4,5,6,7,7a-Hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride    is obtained analogously to the procedure described in example 1c) by    reacting R,R—N-(2-aminocyclohexyl)-N′-(4-methyl-3-thienyl)thiourea    and methyl iodide in anhydrous ethanol as solvent and reaction    medium. Amorphous precipitate which is chromatographed on silica gel    using mixture 4 as mobile phase and crystallized under acetone.    Crystalline solid, m.p. 235-238° C.

EXAMPLE 11trans-S,S-3N-(3a,4,5,6,7,7a-Hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

-   a) trans-S,S-3N-(2-Aminocyclohexyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and    trans-S,S-1,2-diaminocyclohexane by separation by silica gel column    chromatography using mixture 4 as mobile phase, as an amorphous oily    product in addition to a product of higher molecular weight of m.p.    94-102° C. The amorphous product is processed further without    further purification.-   b)    trans-S,S—N-(3a,4,5,6,7,7a-Hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride    is obtained analogously to the procedure described in example 1c) by    reacting S,S—N-(2-aminocyclohexyl)-N′-(4-methyl-3-thienyl)thiourea    and methyl iodide in anhydrous ethanol as solvent and reaction    medium. Amorphous precipitate which is chromatographed on silica gel    using mixture 4 as mobile phase and crystallizes under acetone.    Crystalline solid, m.p. 225-230° C.

EXAMPLE 12 2-Chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride and2,5-dichloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride

are obtained analogously to the procedure described in example 2 from3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride andN-chlorosuccinimide in glacial acetic acid. Column chromatography onsilica gel using mixture 17 as mobile phase results in the separation of2,5-dichloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride(colorless crystalline compound, m.p.: 291° C.) from2-chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride(colorless crystalline compound, m.p. 257-259° C.).

EXAMPLE 132-Chloro-3N-(4-methyl-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

is obtained analogously to the procedure described in example 2 from3N-(4-methyl-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride andN-chlorosuccinimide in glacial acetic acid. Following columnchromatography on silica gel using mixture 17 as mobile phase,2-chloro-3N-(4-methyl-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride is obtained as a colorless to slightly yellowishcrystalline product. M.p. 255-259° C.

EXAMPLE 142-Chloro-3N-(4,5,6,7-tetrafluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

is obtained analogously to the procedure described in example 2: from3N-(4,5,6,7-tetrafluoro-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride and N-chlorosuccinimide in glacial acetic acid.Crystalline product. M.p. 233-235° C.

EXAMPLE 15trans-2-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride (racemate)

is obtained analogously to the procedure described in example 2: from3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride (racemate) and N-chlorosuccinimide in glacial acetic acid.Crystalline product. M.p. 258-260° C.

EXAMPLE 16trans-R,R-2-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride andtrans-R,R-2,5-dichloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

are obtained analogously to the procedure described in example 2: fromtrans-R,R-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride and N-chlorosuccinimide in glacial acetic acid followingchromatographic separation of the two crystalline products in thefollowing order:

-   a)    trans-R,R-2,5-dichloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)    -4-methyl-3-thienylamine hydrochloride, decomposition with foaming    starting at 80° C.,-   b)    trans-R,R-2-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)    -4-methyl-3-thienylamine hydrochloride, crystalline product. M.p.    260-262° C.

EXAMPLE 17trans-S,S-2-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

is obtained analogously to the procedure described in example 2: fromtrans-S,S-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride and N-chlorosuccinimide in glacial acetic acid followingchromatographic separation. Colorless crystalline product, m.p. 258-260°C.

EXAMPLE 18 2-Bromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride and2,5-dibromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride

are obtained analogously to the procedure described in example 2: from3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride andN-bromosuccinimide (instead of N-chlorosuccinimide) in glacial aceticacid. Following column chromatography on silica gel using a mixture of 5parts of dichloromethane, 3 parts of n-heptane, 1 part of glacial aceticacid and 1 part of ethanol (hereinbelow referred to as “mixture 1”) asmobile phase and treatment with a solution of hydrogen chloride gas inether, 2-bromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride, a crystalline product of m.p. 228-231° C., and2,5-dibromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride,a crystalline product of m.p. 208-210° C., are obtained by fractionalcrystallization in ethyl acetate.

EXAMPLE 19trans-R,R-2-Bromo-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride andtrans-R,R-2,5-dibromo-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride

are obtained analogously to the procedure described in example 19: fromtrans-R,R-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride and N-bromosuccinimide in glacial acetic acid. Followingcolumn chromatography on silica gel using mixture 1 as mobile phase, andtreatment with a solution of hydrogen chloride gas in ether,trans-R,R-2-bromo-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride, crystalline product, m.p. 215-218° C. andtrans-R,R-2,5-dibromo-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylaminehydrochloride, crystalline product, m.p. 218-220° C. are obtainedfollowing fractional crystallization in ethyl acetate.

EXAMPLE 20 3N-(4-Chloro-2-benzimidazolylamino)-4-methylthiophenehydrochloride

-   a) N-(2-Amino-3-chlorophenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the reaction described in example 1b)    from 4-methyl-3-thienyl isothiocyanate and    3-chloro-1,2-diaminobenzene (prepared by catalytic hydrogenation of    3-chloro-2-nitroaniline using Pt on activated carbon under    atmospheric pressure at room temperature). Crystalline solid, m.p.    298-305° C.,-   b) 3N-(4-Chloro-2-benzimidazolylamino)-4-methylthiophene    hydrochloride    is obtained analogously to the procedure described in example 1c)    from N-(2-amino-3-chlorophenyl)-N′-(4-methyl-3-thienyl)-thiourea and    methyl iodide. Amorphous precipitate which crystallizes under ethyl    acetate. Crystalline solid, point of decomposition 240-245° C.

EXAMPLE 212-Chloro-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophenehydrochloride

is obtained analogously to the procedure described in example 2 from3N-(4-chloro-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride andN-chlorosuccinimide in glacial acetic acid. Following silica gel columnchromatography using a mixture of 10 parts of methylene chloride and 1part of methanol as mobile phase,2-chloro-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophenehydrochloride is, After crystallization under ethyl acetate, obtained asa colorless to slightly yellowish solid. M.p. 270-272° C.

EXAMPLE 22 2-Bromo-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophenehydrochloride

is obtained analogously to the procedure described in example 2 from3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophene hydrochloride andN-bromosuccinimide (instead of N-chlorosuccinimide) in glacial aceticacid. Following silica gel column chromatography using a mixture of 20parts of ethyl acetate, 10 parts of n-heptane and 3 parts of glacialacetic acid as mobile phase and treatment with a solution of hydrogenchloride gas in ether,2-bromo-3N-(4-chloro-2-benzimidazolylamino)-4-methylthiophenehydrochloride is obtained by fractionated crystallization in ethylacetate in the presence of hydrogen-chloride-saturated ether.Crystalline product of m.p. 278-280° C.

EXAMPLE 23(2-Bromo-4-methylthiophene-3-yl)-(5-fluoro-1H-benzoimidazol-2-yl)aminehydrochloride

(5-Fluoro-1H-benzimidazol-2-yl)-(4-methylthiophene-3-yl)amine (300 mg)(example 1) was dissolved in glacial acetic acid (50 ml). At roomtemperature, N-bromosuccinimide (207 mg) dissolved in glacial aceticacid (10 ml), was slowly added dropwise, with vigorous stirring. Afterthe addition had ended, stirring was continued for another 10 min andthe glacial acetic acid was then distilled off under reduced pressure,and the residue was dissolved in ethyl acetate and washed with saturatedpotassium carbonate solution. The organic phase was dried over magnesiumsulfate, filtered and concentrated. The residue was purified bypreparative chromatography and the product-containing fractions werecombined, freed from acetonitrile, made basic and extracted three timeswith ethyl acetate. The organic phases were combined, dried (MgSO₄) andfiltered. Following removal of the solvent under reduced pressure, waterand 2N hydrochloric acid were added to the residue and the mixture wasfreeze-dried. This gave 245 mg of the desired product.

LCMS-Rt (B): 0.95 min

MS (ES⁺, M+H⁺): 326.09

EXAMPLE 24 2-Bromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophenehydrochloride and2,5-dibromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methyl-thiophenehydrochloride

A solution of 0.161 g of N-bromosuccinimide in 6 ml of glacial aceticacid is added to a solution of 0.214 g of3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophene hydrochloride in 6ml of glacial acetic acid, and the mixture is stirred at roomtemperature for 30 minutes. After removal of the solvent bydistillation, water is added to the residue and the mixture is madealkaline using 2N NaOH and extracted with ethyl acetate. The organicphase is dried, the solvent is distilled off and the residue isseparated by silica gel column chromatography using a mixture of 20parts of ethyl acetate, 10 parts of n-heptane and 3 parts of glacialacetic acid. The hydrochlorides of the two compounds are obtained bydistilling off the fractionated solutions, dissolving the residue inethyl acetate and precipitating the product by addition ofhydrogen-chloride-saturated diethyl ether. Crystallization was promotedby gentle warming.

EXAMPLE 24a2-Bromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophenehydrochloride: colorless crystals; m.p. 212° C. (decomposition). EXAMPLE24b 2,5-Dibromo-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophenehydrochloride: colorless crystals; m.p. 242-244° C. (decomposition).EXAMPLE 25 3N-(5-Methoxy-2-benzimidazolylamino)-4-methylthiophene

-   a) N-(2-Amino-4-methoxyphenyl)-N′-(4-methyl-3-thienyl)thiourea

A mixture of 5.89 g of 4-methylthiophene 3-isothiocyanate and 5 g of4-methoxy-1,2-diaminobenzene in 60 ml of anhydrous THF is stirred atroom temperature for 2 hours, and the solvent is distilled off. Water isadded to the residue, the mixture is extracted with ethyl acetate, thedark solution is treated with activated carbon and the organic solventis re-evaporated. With gentle warming, the residue is treated repeatedlywith diisopropyl ether and the solid is filtered off. Brown crystallinesolid, m.p. 143-146° C.

-   b) A mixture of 2.83 g of    N-(2-amino-4-methoxyphenyl)-N′-(4-methyl-3-thienyl)thiourea,    8.5 g of methyl iodide, and 100 ml of anhydrous ethanol is boiled    under reflux for 5 hours, and the solvent is then distilled off and    water is added to the residue. Using 2N aqueous sodium hydroxide    solution, the mixture is made alkaline and then extracted with ethyl    acetate, the organic phase is treated with water and then with    activated carbon and the product is purified by silica gel column    chromatography using a mobile phase mixture of 20 parts of ethyl    acetate, 10 parts of n-heptane and 3 parts of glacial acetic acid.    This gives 3N-(5-methoxy-2-benzimidazolylamino)-4-methylthiophene as    an amorphous product.

EXAMPLE 26 3N-(5-Methoxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride

is obtained by precipitating a solution of 0.2 g of3N-(5-methoxy-2-benzimidazolyl-amino)-4-methylthiophene (example 25) in10 ml of ethyl acetate using a saturated solution of hydrogen chloridegas and diethyl ether, giving a crystalline precipitate. M.p.: 222-225°C.

EXAMPLE 272-Chloro-3N-(5-methoxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride

For about 2 to 2½ hours, a mixture of 0.519 g of3N-(5-methoxy-2-benzimidazolyl-amino)-4-methylthiophene hydrochloride,0.046 g of N-chlorosuccinimide and 10-15 ml of glacial acetic acid isheated at 45° C. The glacial acetic acid is then distilled off, water isadded to the residue and the mixture is adjusted to pH 9-10 using 2NNaOH. The mixture is extracted with ethyl acetate, the solvent isevaporated and the residue is chromatographed on silica gel on amedium-pressure column using a mixture of 20 parts of ethyl acetate, 10parts of n-heptane and 3 parts of glacial acetic acid. The base obtainedafter removal of the solvent by distillation is, in ethyl acetate,converted into the hydrochloride using saturated ethereal hydrogenchloride solution, and the product is crystallized under ethyl acetate.Crystalline solid m.p.: 182-186° C.

EXAMPLE 282,5-Dichloro-3N-(5-methoxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride

Analogous work-up of a reaction mixture of3N-(5-methoxy-2-benzimidazolylamino)-4-methylthiophene hydrochloride,N-chlorosuccinimide and glacial acetic acid for about 2 to 2½ hours at55° C. gave2,5-dichloro-3N-(5-methoxy-2-benzimidazolylamino)-4-methylthiophene.Crystalline solid, m.p.: 278-282° C.

EXAMPLE 29 3N-(4-Methoxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride

-   a) 3-Methoxy-1,2-diaminobenzene    was obtained as a brown oil by hydrogenation of    2-methoxy-6-nitroaniline using hydrogen gas and Raney nickel as    catalyst at room temperature and a pressure of 3 bar. The product    was converted into the thiourea without further purification.-   b) N-(2-Amino-3-methoxyphenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the procedure described in example 25a)    from 3-methoxy-1,2-diaminobenzene and 4-methyl-3-thienyl    isothiocyanate in anhydrous THF, followed by medium-pressure    chromatography on silica gel using a mixture of 1 part of toluene    and 1 part of ethyl acetate. Crystalline solid, m.p.: 148-153° C.    Solidification of the melt and next m.p. at 260° C.-   c) 3N-(4-Methoxy-2-benzimidazolylamino)-4-methylthiophene    hydrochloride    is obtained analogously to the procedures described in examples 25    and 26 from    N-(2-amino-3-methoxyphenyl)-N′-(4-methyl-3-thienyl)thiourea by    heating with methyl iodide in THF, analogous work-up and treatment    of the benzimidazole with HCl in ether. Crystalline solid, m.p.:    230-235° C.

EXAMPLE 302-Chloro-3N-(4-methoxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride

A mixture of 0.1 g of3N-(4-methoxy-2-benzimidazolylamino)-4-methylthiophene hydrochloride,0.046 g of N-chlorosuccinimide and 10-15 ml of glacial acetic acid isheated at 40° C. for about 2 to 2½ hours. The glacial acetic acid isthen distilled off, water is added to the residue and the pH is adjustedto 9-10 using 2N NaOH. The mixture is extracted with ethyl acetate, thesolvent is evaporated and the residue is chromatographed on silica gelon a medium-pressure column using a mixture of 20 parts of ethylacetate, 10 parts of n-heptane and 3 parts of glacial acetic acid. Theresulting base is, in ethyl acetate, converted into the hydrochlorideusing saturated ethereal hydrogen chloride solution. Colorless tolight-yellow crystalline solid, m.p.: 248-250° C.

EXAMPLE 313N-(4-Chloro-6-trifluoromethyl-2-benzimidazolylamino)-4-methyl-thiophenehydrochloride

-   a)    N-(2-Amino-3-chloro-5-trifluoromethylphenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the procedure described in example 25a)    by reacting 3-chloro-5-trifluoromethyl-1,2-diaminobenzene and    4-methyl-3-thienyl isothiocyanate in anhydrous THF at room    temperature for 3 days. The solvent is distilled off and water is    added to the residue, and the mixture is then extracted with ethyl    acetate, the solvent is again distilled off and the amorphous    residue is crystallized under diisopropyl ether. M.p.: >310° C.-   b)    3N-(4-chloro-6-trifluoromethyl-2-benzimidazolylamino)-4-methylthiophene    hydrochloride    is obtained analogously to the procedures described under examples    25 and 26 from    N-(2-amino-3-chloro-5-trifluoromethylphenyl)-N′-(4-methyl-3-thienyl)thiourea    by boiling with methyl iodide in THF under reflux conditions for 5    hours, analogous work-up and purification by medium-pressure silica    gel column chromatography using a mixture of identical parts by    volume of ethyl acetate and toluene. The solvent is evaporated and    the residue is then dissolved in ethyl acetate, giving, by addition    of a saturated solution of hydrogen chloride in diethyl ether,    3N-(4-chloro-6-trifluoromethyl-2-benzimidazolyl-amino)-4-methylthiophene    hydrochloride as a crystalline precipitate. Solid, m.p.: 210-213° C.

EXAMPLE 322-Chloro-3N-(4-chloro-6-trifluoromethyl-2-benzimidazolylamino)-4-methylthiophenehydrochloride

A mixture of 0.34 g of3N-(4-methoxy-2-benzimidazolylamino)-4-methylthiophene hydrochloride,0.151 g of N-chlorosuccinimide and 20 ml of glacial acetic acid isstirred at room temperature for ½ hour and heated at 60° C. for onehour. The glacial acetic acid is then distilled off, water is added tothe residue and the pH is adjusted to 9-10 using 2N NaOH. The mixture isextracted with ethyl acetate, the solvent is evaporated and the residueis chromatographed on silica gel on a medium-pressure column using amixture of identical parts of toluene and ethyl acetate. The solvent isdistilled off and the resulting base is then, in ethyl acetate,converted into the hydrochloride using saturated ethereal hydrogenchloride solution. Colorless to light-yellow crystalline solid. mp.:247-250° C.

EXAMPLE 33 3N-(4-Carboxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride

-   a) N-(2-Amino-3-carboxyphenyl)-N′-(4-methyl-3-thienyl)thiourea    is obtained analogously to the procedure described in example 25a)    from 3-carboxy-1,2-diaminobenzene and 4-methyl-3-thienyl    isothiocyanate in anhydrous THF, followed by medium-pressure    chromatography on silica gel using a mixture of 12 parts of    methylene chloride and 1 part of methanol. Amorphous product.-   b) 3N-(4-Carboxy-2-benzimidazolylamino)-4-methylthiophene    hydrochloride    is obtained by boiling a solution of 1.12 g of    N-(2-amino-3-carboxyphenyl)-N′-(4-methyl-3-thienyl)thiourea and 3.1    g of methyl iodide in 60 ml of ethanol under reflux. The solvent is    evaporated, water is added to the residue, the pH is adjusted to 5    using 2N aqueous HCl and the precipitate is filtered off.    Crystalline solid, point of decomposition: 265-285° C.

EXAMPLE 342-Chloro-3N-(4-carboxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride

is obtained analogously to the procedure described in example 32 from0.2 g of 3N-(4-carboxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride and 0.103 g of N-chlorosuccinimide in 20-25 ml of glacialacetic acid and precipitation of the corresponding hydrochloride usingHCl-saturated diethyl ether in ethyl acetate and subsequentcrystallization under diisopropyl ether and ethyl acetate. Point ofdecomposition 170° C.

EXAMPLE 353N-[4-(1-Piperidinocarbonyl)-2-benzimidazolylamino]-4-methylthiophenehydrochloride

0.215 g of N,N′-carbonyldiimidazole is added to a mixture of 0.330 g of3N-(4-carboxy-2-benzimidazolylamino)-4-methylthiophene hydrochloride, 30ml of anhydrous THF and 5 ml of anhydrous dimethylacetamide. The mixtureis stirred at room temperature for about 4 hours, when the evolution ofcarbon dioxide has ceased, and 0.411 g of piperidine is then added. Thesolution is stirred at room temperature for 2 hours and, after standingovernight, the solvent is distilled off under reduced pressure. Theresidue is triturated with water, the solid is filtered off anddissolved in ethyl acetate, the insoluble fraction is removed byfiltration and the solvent is distilled off under reduced pressure.Foam-like amorphous product.

EXAMPLE 362-Chloro-4-methyl-3N-[4-(1-piperidinocarbonyl)-2-benzimidazolylamino]-thiophenehydrochloride

A mixture of 0.2 g of3N-[4-(1-piperidinocarbonyl)-2-benzimidazolylamino]-4-methyl-thiophenehydrochloride and 0.086 g of N-chlorosuccinimide in about 20 ml ofglacial acetic acid is stirred at room temperature for 1½ hours and at35° C. for about 30 min, the solvent is distilled off and the residueis, after addition of water, made alkaline using 2N NaOH. Followingextraction with ethyl acetate, the solvent is evaporated and the residueis purified by medium-pressure silica gel column chromatography using amixture of 20 parts of ethyl acetate, 10 parts of n-heptane and 3 partsof glacial acetic acid. The solvent is distilled off, the residue isdissolved in ethyl acetate and the mixture is acidified using a solutionof ether saturated with hydrogen chloride. The amorphous residue iscrystallized under a mixture of ethyl acetate with a little acetone anda little ethanol. Amorphous solid, point of decomposition from 100° C.

EXAMPLE 372-Chloro-3N-(4-fluoro-2-benzimidazolylamino)-4-methylthiophenehydrochloride

0.132 g of N-chlorosuccinimide is added to 0.234 g of3N-(4-fluoro-2-benzimidazolyl-amino)-4-methylthiophene hydrochloride inabout 20 ml of glacial acetic acid and the mixture is stirred at roomtemperature for 30 minutes and at 50-60° C. for another 1½ hours. Theacetic acid is distilled off under reduced pressure, water is then addedto the residue and the pH is adjusted to about 10-11 using 2N NaOH, andthe mixture is extracted with ethyl acetate, which is then distilledoff. The residue is chromatographed on a silica gel column undermedium-pressure conditions using a mixture of 20 parts of ethyl acetate,10 parts of n-heptane and 3 parts of glacial acetic acid. Afterconcentration, the residue is dissolved in a little ethyl acetate andthe hydrochloride is precipitated by addition ofhydrogen-chloride-saturated diethyl ether. Colorless to light-yellowcrystalline solid. M.p.: 268-270° C.

EXAMPLE 382-Chloro-3N-(4-hydroxy-2-benzimidazolylamino)-4-methylthiophenehydrochloride

A suspension of 0.13 g of2-chloro-3N-(4-methoxy-2-benzimidazolylamino)-4-methyl-thiophenehydrochloride in about 20 ml of anhydrous methylene chloride is added toa suspension of 0.29 g of activated anhydrous aluminum chloride in 10 mlof anhydrous methylene chloride, and the reaction mixture is stirred at55° C. for 2 hours. After cooling, the reaction mixture is poured intoice-water and extracted with ethyl acetate, the organic phase is driedover sodium sulfate and the solvent is distilled off. The residue ischromatographed on a silica gel column under medium-pressure conditionsusing a mixture of 20 parts of ethyl acetate, 10 parts of n-heptane and3 parts of glacial acetic acid, and the eluate is concentrated underreduced pressure. The residue is dissolved in ethyl acetate and thehydrochloride is precipitated by addition of hydrogen-chloride-saturateddiethyl ether. Crystalline solid. M.p. 246-248° C.

EXAMPLE 39 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene

is obtained by adding 2N NaOH to a solution of 3 g of2-chloro-3N-(2-benzimidazolyl-amino)-4-methylthiophene hydrochloride in200 ml of water until a pH of 10 is set. The crystals are filtered offand washed repeatedly with water. Yield: 2.52 g. Colorless crystalpowder. M.p. 182-185° C.

EXAMPLE 40 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophenehydrobromide

0.25 g of 2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene isdissolved in 10 ml of ethanol, 0.1 ml of 48% strength HBr is then addedand the mixture is stirred at room temperature for a little while. Thesolvent is distilled off and the residue is crystallized under ethylacetate. Yield: 0.29 g. Colorless crystals, point of decomposition:252-254° C.

EXAMPLE 41 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene adipicacid salt

is obtained analogously to the procedure described in example 40 from2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene using oneequivalent of adipic acid. Colorless crystals. M.p. 155-157° C.

EXAMPLE 42 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene oxalicacid salt

is obtained analogously to the procedure described in example 40 byreacting 2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene with oneequivalent of oxalic acid in ethyl acetate. Colorless crystals. M.p.:220-222° C.

EXAMPLE 43 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophenephosphoric acid salt

is obtained analogously to the procedure described in example 40 from2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene using oneequivalent of phosphoric acid. Colorless crystals. Decomposition range:113-175° C.

EXAMPLE 44(1H-Benzimidazol-2-yl)-(2-chloro-4-methylthiophen-3-yl)methylamine

Finely powdered dry potassium carbonate (66 mg) was added to a solutionof 2-chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine (125 mg, fromexample 39) and dry methanol (20 ml). Methyl iodide (74 mg) was thenadded dropwise with exclusion of moisture and vigorous stirring, and themixture was kept under reflux for three days. The solvent was removedunder reduced pressure and the residue was then partitioned betweenethyl acetate and water, the ethyl acetate phase was dried withmagnesium sulfate, the magnesium sulfate was filtered off and thefiltrate was evaporated to dryness. The product was then purified bypreparative HPLC. The product-containing fractions were combined and,after removing the acetonitrile under reduced pressure, freeze-dried.For further purification, the product was finally chromatographed onsilica gel using ethyl acetate/heptane (¼). The product-containingfractions were combined and then evaporated to dryness, and the residuewas taken up in HCl and freeze-dried. This gave 5 mg of a solid.

LCMS-Rt (A): 2.04 min

MS (ES⁺, M+H⁺): 278.05

EXAMPLE 45(5,6-Difluoro-1H-benzimidazol-2-yl)-(4-methylthiophen-3-yl)aminetrifluoroacetic acid salt

3-Isothiocyanato-4-methylthiophene (1.08 g), dissolved in absolutetetrahydrofuran (30 ml), was added dropwise to a solution of1,2-diamino-4,5-difluorobenzene (1 g) in absolute tetrahydrofuran (20ml). The mixture was then stirred at room temperature for 2 hours andallowed to stand overnight. Methyl iodide (0.44 ml) was added and themixture was then stirred for 8 hours and allowed to stand overnight. Thetetrahydro-furan was then removed under reduced pressure, the residuewas partitioned between ethyl acetate and water, the phases wereseparated and the ethyl acetate phase was dried over magnesium sulfate.The residue was absorbed under silica gel and chromatographed on silicagel using the mobile phase n-heptane:ethyl acetate=1:1. This gave 229 mgof the desired compound as the free base.

An impure fraction from the above chromatography was purified bypreparative HPLC. Following freeze-drying, 42.2 mg of the desiredcompound were isolated as trifluoroacetic acid salt.

LCMS-Rt (A): 1.98 min

MS (ES⁺, M+H⁺): 266.13

EXAMPLE 46(2-Chloro-4-methylthiophen-3-yl)-(5,6-difluoro-1H-benzoimidazol-2-yl)aminehydrochloride

At room temperature, a solution of N-chlorosuccinimide (124.6 mg) inglacial acetic acid (5 ml) was added dropwise to a solution of(5,6-difluoro-1H-benzimidazol-2-yl)-(4-methylthiophen-3-yl)amine (225mg) in glacial acetic acid (5 ml). The mixture was then stirred at roomtemperature for 3.5 hours. The glacial acetic acid was then removed andthe residue was taken up in water and adjusted to pH 10 using 2 Maqueous sodium hydroxide solution. The aqueous phase was extracted threetimes with ethyl acetate, the combined organic phases were dried overmagnesium sulfate and the solvent was removed. The residue was purifiedby preparative chromatography and the product-containing fractions werecombined, freed from acetonitrile, made basic and extracted three timeswith ethyl acetate. The organic phases were combined, dried (MgSO₄),filtered and concentrated. The residue was taken up in water, acidifiedwith 10% strength hydrochloric acid and freeze-dried. This gave 81 mg ofthe desired product as a solid.

LCMS-Rt (A): 2.15 min

MS (ES⁺, M+H⁺): 300.11

EXAMPLE 47(2-Bromo-4-methylthiophen-3-yl)-(5,6-difluoro-1H-benzoimidazol-2-yl)-amine

At room temperature, a solution of N-bromosuccinimide (8 mg) in glacialacetic acid (0.5 ml) was added dropwise to a solution of(5,6-difluoro-1H-benzimidazol-2-yl)-(4-methylthiophen-3-yl)aminetrifluoroacetic acid salt (15 mg, example 45) in glacial acetic acid(0.5 ml) in a ReactiVial, and the mixture was stirred at roomtemperature for 0.5 h. The acetic acid was then removed under reducedpressure and saturated potassium carbonate solution and ethyl acetatewere added to the residue. The organic phase was removed and the aqueousphase was then extracted twice with ethyl acetate. The combined organicphases were dried using magnesium sulfate and the drying agent was thenfiltered off. The residue that remained after removal of the solventunder reduced pressure was purified by preparative chromatography. Theproduct-containing fractions were combined and freed from acetonitrile,saturated sodium bicarbonate solution was added to the residue and themixture was extracted three times with ethyl acetate. The organic phaseswere combined, dried (MgSO₄) and filtered. After removal of the ethylacetate under reduced pressure, the residue was coevaporated withtoluene and then dried under high vacuum. This gave 8.1 mg of thedesired compound.

LCMS-Rt (D): 1.45 min

MS (ES⁺, M+H⁺): 343.96

EXAMPLE 48[(2-Chloro-4-methylthiophen-3-yl)-(4,5,6,7-tetrahydro-1H-benzimidazol-2-yl)]aminehydrochloride

-   a) 1,4-Dioxaspiro[4.5]dec-6-ylamine

The amine required as precursor was prepared in accordance withGB1131191. 2-Chlorocyclohexanone was reacted with phthalimide to give2-(2-oxocyclohexyl)isoindole-1,3-dione, which was ketalized withethylene glycol in the presence of para-toluenesulfonic acid, giving2-(1,4-dioxaspiro[4.5]dec-6-yl)isoindole-1,3-dione. Treatment withhydrazine hydrate to remove the phthalimide radical gave the desired1,4-dioxaspiro[4.5]dec-6-ylamine.

-   b) 1-(1,4-Dioxaspiro[4.5]dec-6-yl)-3-(4-methylthiophen-3-yl)thiourea

A solution of 3-isothiocyanato-4-methylthiophene (296.2 mg, see example1a) in absolute tetrahydrofuran (10 ml) was added dropwise to a solutionof 1,4-dioxa-spiro[4.5]dec-6-ylamine (300 mg) in absolutetetrahydrofuran (10 ml), the mixture was stirred at room temperature for2 hours and the solvent was then removed under reduced pressure. Theresidue was purified by preparative chromatography and theproduct-containing fractions were combined, freed from acetonitrile,made basic and extracted three times with ethyl acetate. The organicphases were combined, dried (MgSO4) and filtered. This gave 428 mg ofthe desired product.

LCMS-Rt (A): 3.57 min

MS (ES⁺, M+H⁺): 313.19

-   c)    1-(1,4-Dioxaspiro[4.5]dec-6-yl)-2-methyl-3-(4-methylthiophen-3-yl)isothiourea

1-(1,4-Dioxaspiro[4.5]dec-6-yl)-3-(4-methylthiophen-3-yl)thiourea (393mg) was dissolved in absolute tetrahydrofuran (8.5 ml), and a solutionof methyl iodide (179 mg) in absolute tetrahydrofuran (0.5 ml) wasadded. The mixture was then stirred at 70° C. in sand bath for 2 days.Ethyl acetate was then added to the reaction mixture, and the mixturewas washed twice with water. The organic phase was dried over magnesiumsulfate and the solvent was removed after filtration. The residue waspurified by preparative chromatography and the product-containingfractions were combined, freed from acetonitrile, made basic andextracted three times with ethyl acetate. The organic phases werecombined, dried (MgSO₄) and filtered. This gave 59 mg of the desiredproduct which was used directly for the next step.

LCMS-Rt (C): 1.05 min

MS (ES⁺, M+H⁺): 327.4

-   d)    N-(1,4-Dioxaspiro[4.5]dec-6-yl)-N′-(4-methylthiophen-3-yl)guanidine

In a ReactiVial, a 7 M solution of ammonia in methanol (2 ml) was addedto1-(1,4-dioxaspiro[4.5]dec-6-yl)-2-methyl-3-(4-methylthiophen-3-yl)isothiourea(58.8 mg), and the mixture was heated in a sand bath at about 100° C.for 16 hours. Removal of the solvent gave a residue of 51 mg of an oilyproduct which was directly reacted further.

LCMS-Rt (C): 1.00 min

MS (ES⁺, M+H⁺): 296.4

-   e)    N-(2-Chloro-4-methylthiophen-3-yl)-N′-(1,4-dioxaspiro[4.5]dec-6-yl)guanidine

N-(1,4-Dioxaspiro[4.5]dec-6-yl)-N′-(4-methylthiophen-3-yl)guanidine (49mg) was dissolved in glacial acetic acid (3 ml), and a solution ofN-chlorosuccinimide (20.3 mg) in glacial acetic acid (5 ml) was addedslowly. The mixture was stirred for a number of hours and then allowedto stand at room temperature over the weekend, after which the glacialacetic acid was removed under reduced pressure, the residue was taken upin water and the mixture was adjusted to pH 10 using 2N sodium hydroxidesolution. The basic phase was extracted three times with ethyl acetateand the combined organic phases were dried over magnesium sulfate,filtered and concentrated. The residue was purified by preparativechromatography and the product-containing fractions were combined, freedfrom acetonitrile, made basic and extracted three times with ethylacetate. The organic phases were combined, dried (MgSO₄) and filtered.Removal of the solvent under reduced pressure gave 24 mg of the desiredproduct which was used directly for the next step.

LCMS-Rt (C): 1.09 min

MS (ES⁺, M+H⁺): 330.4

-   f)    ((2-Chloro-4-methylthiophen-3-yl)-(4,5,6,7-tetrahydro-1H-benzoimidazol-2-yl))amine    hydrochloride

N-(2-Chloro-4-methylthiophen-3-yl)-N′-(1,4-dioxaspiro[4.5]dec-6-yl)guanidine(24 mg) was dissolved in 2N hydrochloric acid (1 ml) and stirred at roomtemperature for 30 min. Concentrated hydrochloric acid (1 ml) was thenadded, and the mixture was stirred for another two hours. The mixturewas then diluted with a little water and freeze-dried. Toluene was addedto the residue and then distilled off under reduced pressure. This stepwas repeated twice, giving 22 mg of the desired product as a solid.

LCMS-Rt (B): 0.95 min

MS (ES⁺, M+H⁺): 268.07

EXAMPLE 49 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophenebenzenesulfonate

2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophene (250 mg) wasdissolved in THF (5 ml), and benzenesulfonic acid (150 mg), dissolved inTHF (5 ml), was added with stirring. After 3 h, the reaction mixture wasleft in the fridge overnight. The precipitate was filtered off withsuction and dried at 75° C. under high vacuum, giving the desiredproduct. Colorless crystals. M.p.: 235° C.

EXAMPLE 50 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophenemethane-sulfonate

was obtained analogously to the procedure described in example 49 from2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene using oneequivalent of methanesulfonic acid. Colorless crystals. M.p.: 227° C.

EXAMPLE 51 2-Chloro-3N-(2-benzimidazolylamino)-4-methylthiophenebenzoate

was obtained analogously to the procedure described in example 49 from2-chloro-3N-(2-benzimidazolylamino)-4-methylthiophene using oneequivalent of benzoic acid. For the precipitation, the reaction mixturewas concentrated to half of its original volume, and ether (30 ml) wasthen added. Colorless crystals, m.p.: 198° C.

EXAMPLE 52 2,4-Dichloro-3N-(2-benzimidazolylamino)thiophenehydrochloride

-   a) Methyl 3-acetylaminothiophene 2-carboxylate

With simultaneous heating in an oil bath, 567 ml of acetic anhydride areadded dropwise to a mixture of 942 g of methyl3-aminothiophene-2-carboxylate and 1000 ml of toluene, and the mixtureis then boiled under reflux conditions for 1½ hours and subsequentlycooled in an ice bath to about 0° C. The crystals are filtered off andwashed twice with a little isopropanol and twice with diisopropyl ether.Methyl 3-acetylaminothiophene-2-carboxylate can be obtained from thefiltrate by further concentration and crystallization. M.p. 93-95° C.

-   b) Methyl 3-acetylamino-4,5-dichlorothiophene-2-carboxylate

With magnetic stirring at a reaction temperature of 20-30° C., 17.9 g ofsulfuryl chloride SO₂Cl₂ are added dropwise to a solution of 19.9 g ofmethyl 3-acetylaminothiophene-2-carboxylate in 100 ml of chloroform. Themixture is then stirred at 40° C. for another 2 hours and boiled underreflux conditions for another 15 minutes. The solvent is distilled offunder reduced pressure, ethyl acetate is then added to the residue andthe crystals are, after standing, filtered off. M.p. 136-138° C.

-   c) Methyl 3-acetylamino-4 chlorothiophene-2-carboxylate

A mixture of 25 g of methyl3-acetylamino-4,5-dichlorothiophene-2-carboxylate, about 10 g oftriethylamine, 300 ml of methanol and 1 g of palladium on carbon is, atroom temperature and under atmospheric pressure, hydrogenated until theuptake of hydrogen has stopped. The catalyst is filtered off and themixture is then concentrated by distillation under reduced pressureuntil crystallization begins, water is then added and the solid isfiltered off. Colorless crystals from isopropanol. M.p. 142-147° C.

-   d) Methyl 3-amino-4-chlorothiophene-2-carboxylate

In a mixture of 50 ml of methanol and 50 ml of concentrated hydrochloricacid, 7 g of methyl 3-acetylamino-4-chlorothiophene-2-carboxylate arestirred at 60° C. for 4 hours, under reflux for 5 hours and at roomtemperature for another 3 days. Any precipitate that has formed isremoved by filtration, and about ⅓ of the volume of the solvent isremoved by distillation under reduced pressure. Following addition ofabout 100 ml of water, the mixture is stirred at room temperature foranother 15 minutes and the colorless crystals are filtered off and driedin a stream of air. M.p.: 62-64° C.

-   e) 3-Amino-4-chlorothiophene

18.02 g of methyl 3-amino-4-chlorothiophene-2-carboxylate are added to asolution of 11.1 g of KOH and 160 ml of water and the mixture is thenboiled under reflux for 3 hours and, after cooling, added dropwise to asolution, which is at 60° C., of 15 ml of concentrated hydrochloric acidand 30 ml of water. This results in a vigorous evolution of CO₂. Afterfurther stirring at 60° C. for about 40 minutes, the mixture is allowedto cool, a layer of 50-100 ml of methyl tert-butyl ether is added, themixture is made alkaline using concentrated aqueous sodium hydroxidesolution and the aqueous phase is extracted in a separating funnel. Theaqueous phase is extracted two more times with methyl tert-butyl ether,and the combined organic extracts are washed once with water in aseparating funnel. The organic phase is dried, the solvent is distilledoff and the oily-amorphous residue is chromatographed on a silica gelcolumn using a mixture of 1 part of ethyl acetate and 1 part of toluene.

-   f) 4-Chloro-3-thienyl isothiocyanate

1.46 g of thiocarbonyldiimidazole are added to a solution of 1.1 g of3-amino-4-chlorothiophene in 20 ml of anhydrous THF, and the mixture isstirred at room temperature for one hour. The solid is distilled offunder reduced pressure, the residue is dissolved in ethyl acetate, theorganic phase is treated twice with water in a separating funnel andthen dried, and the solvent is again distilled off under reducedpressure. This gives 4-chloro-3-thienyl isothiocyanate as a dark oilwhich is then reacted further without further purification steps.

-   g) N-(2-Aminophenyl)-N′-(4-chloro-3-thienyl)thiourea

0.86 g of 1,2-diaminobenzene (o-phenylenediamine) is added to a solutionof 1.4 g of 4-chloro-3-thienyl isothiocyanate in 40 ml of anhydrous THF,the mixture is stirred at room temperature for about 20 hours and thesolvent is distilled off under reduced pressure. The residue is treatedwith water and extracted with ethyl acetate, the solvent is distilledoff again and the residue is purified using medium-pressure silica gelcolumn chromatography using a 1:1 mixture of ethyl acetate and toluene.Brown-yellow solid.

-   h) 4-Chloro-3N-(2-benzimidazolylamino)thiophene

A solution of 0.169 g of sodium hydroxide in 5 ml of water, followed bya solution of 0.363 g of p-toluenesulfonyl chloride in 10 ml of THF, isadded to a solution of 0.5 g ofN-(2-aminophenyl)-N′-(4-chloro-3-thienyl)thiourea in 25 ml of anhydrousTHF. The mixture is stirred at room temperature for 3 hours, the solventis then distilled off under reduced pressure and the residue is treatedwith water and extracted with ethyl acetate. After removal of thesolvent by distillation, the product is purified by medium-pressuresilica gel chromatography using a mixture of 20 parts of ethyl acetate,10 parts of n-heptane and 3 parts of glacial acetic acid as eluent.

For characterization, a small portion of the4-chloro-3N-(2-benzimidazolylamino)-thiophene was, in ethyl acetate,using ethereal hydrogen chloride solution, converted into4-chloro-3N-(2-benzimidazolylamino)thiophene hydrochloride andcharacterized. Colorless crystals. M.p.: 256-260° C.

-   i) 2,4-Dichloro-3N-(2-benzimidazolylamino)thiophene hydrochloride

A solution of 0.16 g of N-chlorosuccinimide in 5 ml of glacial aceticacid is added to a solution of 0.3 g of4-chloro-3N-(2-benzimidazolylamino)thiophene in 10 ml of glacial aceticacid. The reaction mixture is stirred at 40° C. for 15 minutes and atroom temperature for about 4 hours, the acetic acid is then distilledoff under reduced pressure and the residue is treated with water. Themixture is made alkaline using aqueous sodium hydroxide solution andthen extracted with ethyl acetate, the extract is washed with water, theorganic phase is dried and the solvent is distilled off under reducedpressure. The residue is purified under medium-pressure conditions bycolumn chromatography using a mixture of 20 parts of ethyl acetate, 10parts of n-heptane and 3 parts of glacial acetic acid as eluent and thenprecipitated from ethyl acetate by addition of a solution of hydrogenchloride in diethyl ether. Colorless crystalline product. M.p. 264-268°C.

EXAMPLE 53 2-Bromo-4-chloro-3N-(2-benzimidazolylamino)thiophenehydrochloride

A solution of 0.356 g of N-bromosuccinimide in 6 ml of glacial aceticacid is added dropwise to a solution of 0.5 g of4-chloro-3N-(2-benzimidazolylamino)thiophene in 15 ml of glacial aceticacid, and the mixture is stirred at room temperature for another 15minutes. The solvent is distilled off and the residue is treated withwater and made alkaline using aqueous sodium hydroxide solution.Following extraction with ethyl acetate, the organic phase is washedwith water, dried and concentrated under reduced pressure. The residueis chromatographed on silica gel using medium-pressure conditions and amixture of 20 parts of ethyl acetate, 10 parts of n-heptane and 3 partsof glacial acetic acid as eluent. Following distillative removal of thesolvent, the residue is taken up in ethyl acetate and2-bromo-4-chloro-3N-(2-benzimidazolyl-amino)thiophene hydrochloride isprecipitated by addition of a solution of hydrogen chloride gas indiethyl ether. Colorless crystalline product. M.p.: 264-266° C.

EXAMPLE 54(2,4-Dichloro-thiophen-3-yl)-(5-fluoro-1H-benzoimidazol-2-yl)-amine-hydrochloride

-   a) 1-(2-Amino-4-fluoro-phenyl)-3-(4-chloro-thiophen-3-yl)-thiourea

4-Fluoro-1,2-phenylendiamine (900 mg) was dissolved in THF (25 ml) and4-chloro-3-thienylisothiocyanat (example 52c), dissolved in THF (15 ml),was added with stirring. The solution was stirred for about 3 h at roomtemperature and stood overnight. Then the reaction mixture wasconcentrated und the residue purified by preparative HPLC. The productcontaining fractions were combined, the acetonitrile was removed, theaqueous residue made basic and three times extracted with ethyl acetate.The organic layers were combined, dried (MgSO4) and filtered. Afterremoval of the solvent the desired product (625 mg) was obtained.

LCMS-Rt (F): 1.28 min

MS (ES⁺, M+H⁺): 302.0

-   b) (4-Chloro-thiophen-3-yl)-(5-fluoro-1H-benzoimidazol-2-yl)-amine

1-(2-Amino-4-fluoro-phenyl)-3-(4-chloro-thiophen-3-yl)-thiourea (625 mg)was dissolved in THF and a solution of NaOH (0.207 g) in water (9 ml)was added. Within 5 min a solution of p-toluenesulfonyl chloride (0.395g) in THF (10 ml) was added dropwise. After stirring for one hour atroom temperature water and ethyl acetate were added to the reactionmixture. The organic layer was separated and the aqueous phase wasextracted three times with ethyl acetate. The combined organic layerswere dried (MgSO4), treated with charcoal, filtered and the solventevaporated to yield the desired product (135 mg).

LCMS-Rt (F): 0.90 min

MS (ES⁺, M+H⁺): 268.0

-   c)    (2,4-Dichloro-thiophen-3-yl)-(5-fluoro-1H-benzoimidazol-2-yl)-amine    hydrochloride

(4-Chloro-thiophen-3-yl)-(5-fluoro-1H-benzoimidazol-2-yl)-amine (85 mg)was dissolved in acetic acid (4 ml) and under vigorous stirring at roomtemperature a solution of N-chlorosuccinimide (42 mg) in acetic acid (4ml) was added. After stirring for 45 min. at room temperature, stirringwas continued for 5 h at 50° C. After the addition of furtherN-chlorosuccinimide (4 mg) stirring was continued for one hour at 50° C.Then the reaction mixture was treated with toluene (20 ml) and solventmixture distilled off. The residue was dissolved in ethyl acetate andwashed with saturated potassium carbonate solution. The organic layerwas dried (MgSO4), filtered and concentrated. The residue was purifiedby preparative HPLC, the product containing fractions were combined, theacetonitrile was removed, the aqueous residue made basic and extractedthree times with ethyl acetate. The organic layers were combined, dried(MgSO4) and filtered. After removal of the solvent water and 2 N HClwere added to the residue. After freeze drying the desired product (17mg) was obtained.

LCMS-Rt (E): 2.65 min

MS (ES⁺, M+H⁺): 301.93

EXAMPLE 55(2-Bromo-4-chloro-thiophen-3-yl)-(5-fluoro-1H-benzoimidazol-2-yl)-aminehydrochloride

(4-Chloro-thiophen-3-yl)-(5-fluoro-1H-benzoimidazol-2-yl)-amine (50 mg,example 54b) was dissolved in acetic acid (4 ml) and at room temperaturewith vigorous stirring N-bromosuccinimide (33 mg) dissolved in aceticacid (4 ml) was slowly added. After stirring for 45 min at roomtemperature toluene (20 ml) was added and the solvent mixture distilledoff. The residue was dissolved in ethyl acetate and washed withsaturated potassium carbonate solution. The organic layer was dried(MgSO4), filtered and concentrated. The residue was purified bypreparative HPLC, the product containing fractions were combined, theacetonitrile was removed, the aqueous residue set basic and three timesextracted with ethyl acetate. The organic layers were combined, dried(MgSO4) and filtered. After removal of the solvent water and 2 N HClwere added to the residue. After freeze drying the desired product (27mg) was obtained.

LCMS-Rt (E): 2.29 min

MS (ES⁺, M+H⁺): 347.87

EXAMPLE 56(2,4-Dichloro-thiophen-3-yl)-(5,6-difluoro-1H-benzoimidazol-2-yl)-amine-hydrochloride

-   a)    1-(2-Amino-4,5-difluoro-phenyl)-3-(4-chloro-thiophen-3-yl)-thiourea

To 1,2-diamino-4,5-difluorobenzene (1.02 g) in THF abs. (15 ml)4-chloro-3-thienylisothiocyanate (1.25 g, example 52c) dissolved in THFabs. (15 ml) was added. Following the analogous description in example54a) the desired product was obtained (773 mg).

LCMS-Rt (F): 1.32 min

MS (ES⁺, M+H⁺): 320.0

-   b)    (4-Chloro-thiophen-3-yl)-(5,6-difluoro-1H-benzoimidazol-2-yl)-amine

To 1-(2-amino-4,5-difluoro-phenyl)-3-(4-chloro-thiophen-3-yl)-thiourea(773 mg) in THF (20 ml) a solution of NaOH (240 mg) in water (9 ml) wasadded followed by a solution of p-toluenesulfonyl chloride (528 mg) inTHF (10 ml). Following the analogous description in example 54b) thedesired product (275 mg) was obtained.

LCMS-Rt (F): 0.95 min

MS (ES⁺, M+H⁺): 286

-   c)    (2,4-Dichloro-thiophen-3-yl)-(5,6-difluoro-1H-benzoimidazol-2-yl)-amine-hydrochloride

To (4-chloro-thiophen-3-yl)-(5,6-difluoro-1H-benzoimidazol-2-yl)-amine(125 mg) in acetic acid (8 ml) a solution of N-chlorosuccinimide (59 mg)in acetic acid (2 ml) was added. Following the analogous description inexample 54c) the desired product (58 mg) was obtained.

LCMS-Rt (E): 2.97 min

MS (ES⁺, M+H⁺): 319.88

EXAMPLE 57(2-Bromo-4-chloro-thiophen-3-yl)-(5,6-difluoro-1H-benzoimidazol-2-yl)-amine-hydrochloride

To (4-chloro-thiophen-3-yl)-(5,6-difluoro-1H-benzoimidazol-2-yl)-amine(125 mg, example 55b) in acetic acid (8 ml) N-bromosuccinimide (78 mg)dissolved in acetic acid was added under vigorous stirring at roomtemperature. Following the analogous description in example 55) thedesired product (77 mg) was obtained.

LCMS-Rt (E): 2.39 min

MS (ES⁺, M+H⁺): 365.86

EXAMPLE 58 4-Chloro-3N-(4-methyl-2-benzimidazolyl-amino)thiopheneHydrochloride

-   a) N-(2-Amino-3-methylphenyl)-N′-(4-chloro-3-thienyl)thiourea    was obtained as described in example 52 g) by using    4-chloro-3-thienylisothiocyanate and 1,2-diamino-3-methylbenzene and    chromatographical purification (silica gel, ethyl    acetate/n-heptane/glacial acetic acid=20:10:3). Brownish-yellowish    solid, Mp.: 193-196° C.-   b) e) 4-Chloro-3N-(4-methyl-2-benzimidazolylamino)thiophene    was obtained as described in example 52h) by using    N-(2-Amino-3-methylphenyl)-N′-(4-chloro-3-thienyl)thiourea and    chromatographical purification (silica gel,    dichloromethane/methanol=10:1). The amorphous, foamy material was    dissolved in ethyl acetate and treated with a solution of gaseous    HCl in diethyl ether forming    4-chloro-3N-(4-methyl-2-benzimidazolylamino)thiophen hydrochloride.    Crystalline material, m.p. 325-327° C.

EXAMPLE 59 2,4-Dichlor-3N-(4-methyl-2-benzimidazolyl-amino)thiophenHydrochloride

was obtained as described in example 52i) by reaction of4-chloro-3N-(4-methyl-2-benzimidazolylamino)thiophene andN-chlorosuccinimide in pure acetic acid and by analogous purification.Crystalline material, m.p. 296-298° C.

EXAMPLE 60trans-(3aS,7aS)-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamineHydrochloride

-   a)    trans-S,S-3N-(2-Amino-cyclohexyl)-N′-(4-chloro-3-thienyl)-thiourea    was obtained as described in example 1b) by reaction of    4-chloro-3-thienyl-isothiocyanate and    trans-S,S-1,2-diaminocyclohexane. Chromatographical purification    (silica gel, ethyl    acetate/dichloromethane/n-heptane/methanol/aqueous ammonia    [35%]=10:5:5:5:1) results in a dark amorphous material which was    used for further syntheses without further purification.-   b)    trans-(3aS,7aS)-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamine    was obtained as described in example 52h) by using    trans-S,S-3N-(2-amino-cyclohexyl)-N′-(4-chloro-3-thienyl)-thiourea    and p-Toluolsulfonylchloride. Chromatographical purification (silica    gel, dichloromethane/methanol=10:1) results in an amorphous material    which can be transformed to the corresponding    trans-S,S-4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamine    hydrochloride by dissolving in ethyl acetate and treatment with a    solution of gaseous HCl in diethylether. Crystalline material, m.p.    196-200° C.

EXAMPLE 61trans-(3aR,7aR)-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamineHydrochloride

-   a)    trans-(1R,2R)-3N-(2-Amino-cyclohexyl)-N′-(4-chloro-3-thienyl)-thiourea    was obtained as described in example 1b) by reaction of    4-chloro-3-thienyl-isothiocyanate und    trans—(1R,2R)-(−)-1,2-diaminocyclohexane. Chromatographical    purification (silica gel, ethyl    acetate/dichloromethane/n-heptane/methanol/aqueous ammonia    [35%]=10:5:5:5:1) results in a dark amorphous material which was    used for further syntheses without further purification.-   b)    trans-(3aR,7aR)-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamine    was obtained as described in example 52h) by using of    trans-R,R-3N-(2-amino-cyclohexyl)-N′-(4-chloro-3-thienyl)-thiourea    and p-toluolsulfonylchloride. Chromatographical purification (silica    gel, ethyl acetate/dichloromethane/n-heptane/methanol/aqueous    ammonia [35%]=10:5:5:5:1) results in an amorphous material which can    be transformed to the corresponding    trans-R,R-4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamine    hydrochloride by dissolving the material in ethyl acetate and    treatment with a solution of gaseous HCl in diethylether.    Crystalline material, m.p. 240-244° C.

EXAMPLE 62cis-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamineHydrochloride

-   a) cis-3N-(2-Amino-cyclohexyl)-N′-(4-chloro-3-thienyl)-thiourea    was obtained as described in example 1b) by reaction of    4-chloro-3-thienyl-isothiocyanate und cis-1,2-diaminocyclohexane.    Chromatographical purification (silica gel, ethyl    acetate/dichloromethane/n-heptane/methanol/aqueous ammonia    [35%]=10:5:5:5:1) results in a dark amorphous material which was    used for further syntheses without further purification.-   b)    cis-4-Chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamine    was obtained as described in example 52h) by using    3N-(cis-2-Amino-cyclohexyl)-N′-(4-chlor-3-thienyl)-thioharnstoff and    p-Toluenesulfonyl chloride. Chromatographical purification (silica    gel, ethyl acetate/dichloromethane/n-heptane/methanol/aqueous    ammonia [35%]=10:5:5:5:1) results in an amorphous brownish material    which can be transformed to the corresponding    4-chloro-3N-(cis-3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamine    hydrochloride by dissolving in ethyl acetate and treatment with a    solution of gaseous HCl in diethylether. Crystalline material, m.p.    228-231° C.

EXAMPLE 63trans-R,R-2,4-Dichloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamineHydrochloride

was obtained as described in example 52i) by reaction oftrans-R,R-4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamineand N-chlorosuccinimide in pure acetic acid and by analogouspurification. Crystalline material, m.p. 296-298° C.

EXAMPLE 64cis-2,4-Dichloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamineHydrochloride

was obtained as described in example 52i) by reaction ofcis-4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamineand N-chlorosuccinimide in pure acetic acid and by analogouspurification. Crystalline material, m.p. 270-274° C.

EXAMPLE 65 4-Chloro-3N-(4-chloro-2-benzimidazolylamino)thiopheneHydrochloride

-   a) 1-N-(2-Amino-3-chlorophenyl)-3-N-(4-chloro-3-thienyl)thiourea    was obtained as described in example 1b) by reaction of    4-chloro-3-thienyl-isothiocyanate und 3-chloro-1,2-diaminobenzene.    The compound crystallizes after stirring in diisopropylether. Solid    crystalline material with 2 melting points: 1^(st) m.p. 152-155° C.;    2^(nd) m.p. (after recrystallization of molten material)>310° C.-   b) 4-Chloro-3N-(4-chloro-2-benzimidazolylamino)thiophene    was obtained as described in example 52h) using    1-N-(2-amino-3-chlorophenyl)-3-N-(4-chloro-3-thienyl)thiourea and    p-toluenesulfonyl chloride. After chromatographic purification    (silica gel, toluene/ethyl acetate=3:1) the product was transformed    to 4-chloro-3N-(4-chloro-2-benzimidazolylamino)thiophene    hydrochloride by dissolving in ethyl acetate and treatment with a    solution of gaseous HCl in diethylether. Crystalline material, m.p.    276-280° C.

EXAMPLE 66 2,4-Dichloro-3N-(4-chloro-2-benzimidazolyl-amino)thiopheneHydrochloride

was obtained as described in example 52i) by reaction of4-chloro-3N-(4-methyl-2-benzimidazolylamino)thiophene andN-chlorosuccinimide in pure acetic acid and by analogous purification.Crystalline material, m.p. 294-297° C.

Analogously to the compounds listed in the working examples, it ispossible to prepare the following thiophene derivatives:

-   2-bromo-4-chloro-3N-(4-methyl-2-benzimidazolyl-amino)thiophen    hydrochloride,-   2-bromo-4-chloro-3N-(4-chlor-2-benzimidazolyl-amino)thiophen    hydrochloride,    trans-R,R-2-bromo-4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamin    hydrochloride,-   trans-(3aS,7aS)-2-bromo-4-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamin    hydrochloride,-   2,4-dibromo-3N-(2-benzimidazolyl)-3-thienylamine hydrochloride,-   2,4-dimethyl-3N-(2-benzimidazolyl)-3-thienylamine hydrochloride,-   2,4-dimethyl-3N-(4-methyl-2-benzimidazolyl)-3-thienylamine    hydrochloride,-   2,4-dimethyl-3N-(5-fluoro-2-benzimidazolyl)-3-thienylamine    hydrochloride,-   2-chloro-3N-(4-butoxy-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride,-   2-chloro-3N-(4-trifluoromethyl-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride,-   2-chloro-3N-(4-methylsulfonyl-2-benzimidazolyl)-4-methyl-3-thienylamine    hydrochloride.

Pharmacological Data:

Test Description:

In this test, the recovery of the intracellular pH (pHi) after anacidification, which starts when the NHE is capable of functioning, evenunder bicarbonate-free conditions, was determined. For this purpose, thepHi was determined using the pH-sensitive fluorescent dye BCECF(Calbiochem, the precursor BCECF-AM is employed). The cells wereinitially loaded with BCECF. The BCECF fluorescence was determined in a“ratio fluorescence spectrometer” (Photon Technology International,South Brunswick, N.J., USA) with excitation wavelengths of 505 and 440nm and an emission wavelength of 535 nm, and was converted into the pHiusing calibration plots. The cells were incubated in NH₄Cl buffer (pH7.4) (NH₄Cl buffer: 115 mM NaCl, 20 mM NH₄Cl, 5 mM KCl, 1 mM CaCl₂, 1 mMMgSO₄, 20 mM Hepes, 5 mM glucose, 1 mg/ml BSA; a pH of 7.4 isestablished with 1 M NaOH) even during the BCECF loading. Theintracellular acidification was induced by addition of 975 μl of anNH₄Cl-free buffer (see below) to 25 μl aliquots of the cells incubatedin NH₄Cl buffer. The subsequent rate of pH recovery was recorded in thecase of NHE1 for two minutes, in the case of NHE2 for five minutes andin the case of NHE3 for three minutes. To calculate the inhibitory powerof the tested substances, the cells were initially investigated inbuffers in which complete or absolutely no pH recovery took place. Forcomplete pH recovery (100%), the cells were incubated in Na⁺-containingbuffer (133.8 mM NaCl, 4.7 mM KCl, 1.25 mM CaCl₂, 1.25 mM MgCl₂, 0.97 mMNa₂HPO₄, 0.23 mM NaH₂PO₄, 5 mM Hepes, 5 mM glucose, a pH of 7.0 isestablished with 1 M NaOH). To determine the 0% value, the cells wereincubated in an Na⁺-free buffer (133.8 mM choline chloride, 4.7 mM KCl,1.25 mM CaCl₂,1.25 mM MgCl₂, 0.97 mM K₂HPO₄, 0.23 mM KH₂PO₄, 5 mM Hepes,5 mM glucose, a pH of 7.0 is established with 1 M KOH). The substancesto be tested were made up in the Na+-containing buffer. Recovery of theintracellular pH at each tested concentration of a substance wasexpressed as a percentage of the maximum recovery. Using the Sigma-Plotprogram, the IC50 value of the substance in question was calculated forthe individual NHE subtypes using the percentages for pH recovery.

Results:

Example IC₅₀ [μM] 16 0.27 (rNHE3)trans-R,R-2-chloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride 12 0.12 (rNHE3)2-chloro-3N-(2-benzimidazolyl)-4-methyl-3-thienylamine hydrochloride 54:0.22 (hNHE3) 2-bromo-4-chloro-3N-(2-benzimidazolylamino)thiophenhydrochloride 53: 0.14 (hNHE3)2,4-dichloro-3N-(2-benzimidazolylamino)thiophen hydrochloride 56: 0.22(hNHE3) 2,4-dichloro-3N-(4-methyl-2-benzimidazolyl- amino)thiophenhydrochloride 60: 0.19 (hNHE3)trans-R,R-2,4-dichloro-3N-(3a,4,5,6,7,7a-hexahydro-1H-2-benzimidazolyl)-3-thienylamin hydrochloride 63: 0.54 (hNHE3)2,4-dichloro-3N-(4-chloro-2-benzimidazolyl- amino)thiophen hydrochloride38: 0.84 (hNHE3) 2-chloro-3N-(4-hydroxy-2-benzimidazolyl-amino)-4-methylthiophen hydrochloride 18: 0.12 (hNHE3)2-bromo-3N-(2-benzimidazolyl)-4-methyl-3-thienylamin hydrochloride 19:0.56 (hNHE3) trans-R,R-2-bromo-3N-(3a,4,5,6,7,7a-Hexahydro-1H-2-benzimidazolyl)-4-methyl-3-thienylamin hydrochloride 2: 0.62 (hNHE3)2-chloro-3N-(5-fluoro-2-benzimidazolyl)-4-methyl-3- thienylaminhydrochloride 44: 1.59 (hNHE3)(1H-benzimidazol-2-yl)-(2-chloro-4-methyl-thiophen-3- yl)-methyl-amineWhile there have been described and pointed out fundamental novelfeatures of the invention as applied to a preferred embodiment thereof,it will be understood that various omissions and substitutions andchanges, in the form and details of the packages and methodsillustrated, may be made by those skilled in the art without departingfrom the invention. For example, it is expressly intended that allcombinations of those elements and/or method steps which performsubstantially the same function in substantially the same way to achievethe same results are within the scope of the invention.

The invention is not limited by the embodiments described above whichare presented as examples only but can be modified in various wayswithin the scope of protection defined by the appended patent claims.

1. A method for the treatment of disorders of the central nervous systemselected from the group consisting of anxiety and depression, comprisingthe administration of a pharmaceutical composition to a patient in needthereof consisting essentially of a compound of formula I or apharmaceutically acceptable salt thereof

wherein: R1 and R2 are independently selected from the group consistingof H, F, Cl, Br, I, CN, NO₂, —(X)_(n)—C_(q)H_(2q)-Z, cycloalkyl having3, 4, 5 or 6 carbon atoms, alkenyl having 2, 3 or 4 carbon atoms,alkenylalkyl having 3 or 4 carbon atoms, ethynyl and alkylalkynyl having3 or 4 carbon atoms, wherein n is zero or 1; X is oxygen, NH, N—CH₃, orS(O)_(k), wherein k is zero, 1 or 2; q is zero, 1, 2, 3, 4, 5 or 6; andZ is hydrogen or C_(m)F_(2m+1), wherein m is zero, 1, 2, 3 or 4; R3 ishydrogen, methyl, F, Cl, Br, I, CN, S(O)_(k)—CH₃, —NO₂, or —O—CH₃,wherein k is zero, 1 or 2; R4 is selected from the group consisting ofhydrogen, cycloalkyl having 3, 4, 5, or 6 carbon atoms, alkenyl having2, 3 or 4 carbon atoms, alkenylalkyl having 3 or 4 carbon atoms,ethynyl, alkylalkynyl having 3 or 4 carbon atoms, and —C_(r)H_(2r)—Y,wherein r is zero, 1, 2, 3 or 4; and Y is hydrogen or trifluoromethyl;R5 and R6 are hydrogen atoms or are together a bond; R7 and R8 areindependently selected from the group consisting of (C₃-C₅)-alkyl,(C₂-C₅)-alkenyl, (C₂-C₅)-alkynyl, (C₃-C₆)-cycloalkyl and(C₄-C₆)-cycloalkenyl; or R7 and R8 together with the two carbon atoms towhich R7 and R8 are attached, form a (C₅-C₁₀) cycloalkyl ring which maybe unsubstituted or substituted with one or more fluorine atoms; or R7and R8 together with the two carbon atoms to which R7 and R8 areattached, form a ring of the following formula;

wherein R10 and R11 are independently selected from the group consistingof hydrogen, fluorine, chlorine, bromine, methyl, CN, OH, —O—CH₃, NO₂,NH₂ and —CF₃; R9 and R12 are hydrogen or F; or R9 is hydrogen and R12 isselected from the group consisting of F, Cl, Br, I, CN, NO₂, COOH,CO—NR13R14, SO₂—NR13R14, alkenyl having 2, 3 or 4 carbon atoms,alkenylalkyl having 3 or 4 carbon atoms, ethynyl, alkylalkynyl having 3or 4 carbon atoms, and —(XI)_(n)—C_(q)H_(2q)-Z; or R12 is hydrogen andR9 is selected from the group consisting of F, Cl, Br, I, CN, NO₂, COOH,CO—NR13R14, SO₂—NR13R14, alkenyl having 2, 3 or 4 carbon atoms,alkenylalkyl having 3 or 4 carbon atoms, ethynyl, alkylalkynyl having 3or 4 carbon atoms, and —(XI)_(n)—C_(q)H_(2q)-Z; wherein: R13 is hydrogenor alkyl having 1, 2, 3 or 4 carbon atoms and R14 is hydrogen or alkylhaving 1,2,3, or 4 carbon atoms; or R13 and R14 together with thenitrogen to which they are attached form a saturated 5-, 6- or7-membered ring; n is zero or 1; XI is oxygen, NH, N—CH₃, or S(O)_(k); kis zero, 1 or 2; q is zero, 1, 2, 3, 4, 5 or 6; and Z is hydrogen orC_(m)F_(2m+1), wherein m is zero, 1, 2, 3 or
 4. 2. The method of claim1, wherein the disorder is anxiety.